Y Store | TOP | STORE | DSSF3 | Mmlib | FAQ | Support | Contact Us |

Sound measurement software 
Frequently asked questions (FAQ) and answers

| Japanese | English |

We have received a lot of questions about our sound measurement software, DSSF3, RAL (Realtime Analyzer Light), RAD (Realtime Analyzer DSS), and RAE (Realtime Analyzer ENA). Common questions and answers are collected in this page. To search this page, select "Find" from the browser's "Edit" menu and enter the phrase you would like to find.


Category of questions


Category: Installation, online update

Installation

I can't install the program. When I run the installer, I get a message INST MSIA.EXE NOT FOUND. What should I do?

How should I install the program when a PC to download the program is different from a PC to install it?

How can I re-install the program?

What can I do to use the program after formatting the hard disk?

I want to upgrade from RAL to RAD. Should I uninstall RAL before install RAD?

I want to use software in other PC. How can I do it?

After trial, I want to change my OS and disk partition. Is there any problems with it?

Is there a way to extend the trial period?

Online update

What is the online update?

How much does it cost for the online update?

Is the online update available during the trial period?

How can I update the program when I cannot connect to the Internet?

Online update fails in DSSF3.

Contents

Category: License and registration

Please tell me how to buy the software and how to make a registration.

I am using RAL, but I want to version up to RAE. What should I do?

Can I receive an invoice or an official purchase order?

I want to have a software in a CD-ROM because I often format the hard disk. How can I do it?

I have purchased your software, but I haven't received it.

I sent you my hard key, but I have not received my registration number from you yet. What is the problem?

Is the hard key changed if I uninstall the program, reinstall OS, or format the hard disk?

Do I need to purchase a license again when the software is reinstalled?

Category: Specification of the software

System requirement

What is the hardware and software requirement?

Realtime Analyzer (RA)

Input device

In RA or EA, input volume is controlled by the slider. If this volume is changed, input level changes and so the precise measurement could not be performed. What can I do?

Why only the display of an input of a peak level monitor can be changed between ON and OFF?

Show me the block diagram of the software. In the diagram, indicate the "input volume" and the "input/output monitor".

Tell me the difference between the "mic" and the "line in" for the input device setting.

Oscilloscope

What is the frequency range of the oscilloscope?

What is the unit of the level range in the oscilloscope?

FFT Analyzer

Please tell me how smoothing and moving average affect the measurement results.

I have a question about Data Record for the Octave Band function of the FFT Analyzer.

Can the FFT Analyzer use text based microphone calibration files?

Is there a way to use different weighting types (X, Inverse X, or a custom weighting)?

Can the FFT Analyzer use a calibration file for the sound card to calibrate out the response of the sound card?

Could You explain what does Frequency Weighting mean?

How can I obtain the RMS value of the recorded waveform?

Why is the data in the Data Record window different from the "Level [dB]" value in the Octave band display?

What is the lowest frequency which can be measured in the Spectrum?

Can I use a peak hold of the spectrum RAL?

When I measured spectra of a "silent" wav file, I got different noise levels in different computers. What is the reason?

Can DSSF3 measure the phase spectrum or the group delay?

Signal generator

When generating the sweep signal and measuring the loudspeaker output in the spectrum, the difference between low and high frequencies becomes large (above 15 dB). What is the reason of this difference?

Recorder

What length of data can be measured?

Impulse response measurement

Does the DSSF3 perform STI calculations automatically?

What is the difference of 1ch and 2ch in the impulse response measurement?

In the impulse response, how can I read the phase delay in each frequency?

Can I export a raw impulse response data (before normalization) as a .wav format?

I checked a frequency characteristics (spectrum) of the impulse response by SA. Also I output the same impulse response data from RA as a .wav format and calculated a spectrum by MATLAB. Problem is that these two spectra are different.

I can't test or perform any analysis on my impulse response wave file

Export and print of the measured data

I want to attach the sound waveform measured by the oscilloscope on a MS Word document.

Is it possible to export the 3D graph of the FFT analyzer to the other software (e.g. MS-Excel)?

Can the measured data by such as the spectrum and the octave band analysis be printed?

Can the spectrum be saved as a numerical data?

In the THD analyzer can I acquire the numerical data?

Can the measurement results of RA (spectrum, octave analysis, and so) or SA be exported to other software (Excel)? Now I use PrintScreen to copy the window image.

Keyboard shortcut and preset

Can I control the window position or start measurements by external command or keyboard shortcut in RAL?

Can I save and load parameter settings instantly for future measurements?

Sound Analyzer (SA)

What kind of 'window', FFT size and percentage of overlap are used for calculating the spectrum in SA?

Environmental noise analyzer (EA)

In the Environmental noise analyzer, the sound pressure level (SPL) is displayed in minus value. How can I change this to display the absolute sound level?

Contents

Category: Equipments

Soundcard

I installed Roland EDIROL (UA-5) as a USB sound device. But when I start RAL, a message "can't use mixer" appears and it does not work. What should I do?

USB sound device does not work with RAE.

Microphone

Can I perform a measurement using the built-in microphone of PC? Or should I use additional equipments?

Should I use the microphone amplifier for the measurement?

What kind of microphone is recommended for the sound measurement?

I want to analyze a sound from a wristwatch. What kind of microphone should be used?

Other

What equipments do I need for audio measurement?

What equipment is necessary for measuring noise?

I want to measure a car audio system by using RAL. If I use a test CD (pink noise or tone) for the measurement, is it OK that only input is available in my soundboard?

Contents

Category: Error message and trouble shooting

Error message "RTA.exe has encountered a problem and needs to close. We are sorry for the inconvenience."

What should I do if the program is hung by the problem of the OS or the driver?

All of a sudden, the font type and size was changed and also the window size was changed.

When I start the program, a dialog "Can't use mixer." is displayed and the program does not start. Can I ask your advice about this?

When I clicked on the shortcut icon to start the program, the following message was displayed and the program was not able to start. Cabinet file 'Data Cab' is not found. PcAudioLTE.exe can not be installed. Please advise me.

I updated my program through internet. After this, a message "licence.dll is not found" always appears when the program starts.

I am trying to use a PCMCIA sound card with RAD, but it does not work. The sound card does not appears in RA's input / output device selector. What should I do?

RAD does not work. The following message always appears. What should I do? "Error message: The specified format is not supported or cannot be translated. Use the capabilities function to determine the supported formats."

Contents

Category: Backup of the measurement data

Show me how to back up my data.

How can we delete specific data files in the Sound Analyzer program?

Contents

Category: How to select the software

What is the minimum package (software + hardware) for measuring noise 
level?

The difference of the version of your software (RAL, RAD, RAE, DSSF3, etc.) is unclear.

What kind of measurements are possible in RAL? 

What is the difference of DSSF3 and RAE?

I want to measure the performance of my handmade audio amplifier. Which version of the software is suited for this purpose?

Which version of the software is suited for measuring the reverberation time from the impulse response?

I want to try visualizing and classifying some "metallic sound". Which software is the best for this kind of measurement?

I want to analyze a snore sound. I also need a realtime analyzer (time / energy / frequency analysis). Which version of software is suited for this purpose?

Do you have a low price software equipped with a distortion analyzer?

I want to measure the frequency response of my self build speaker system. Which software is required? Do I need any other device?

Which software is suitable for a design of speaker crossover network?

What software is suitable for noise measurement?

Contents

Category: Application in specific fields

Audio measurement

How can I use the software for the adjustment of the listening room?

Is it possible in RAL to observe the waveform of the amplifier output?

How can I measure the sensitivity and the frequency response of microphones using your software?

Can I output a measurement data of RAL to a video deck as a movie in real time?

I want to measure the frequency response of my car audio system at the driver's position. Which software is suitable for this kind of measurement?

How can I compensate the microphone's frequency response for this measurement for equalizing audio system?

How can I use the software for adjusting the crossover network, positioning the loudspeakers, and testing the amplifier?

How can I measure sound by the octave band analysis and save the data?

Can I measure the performance of speaker network itself?

I use RAL for setting up a self-built car audio system. Please give me some advice.

Can RAL be used for the adjustment of time alignment of loudspeaker?

Can DSSF3 be used for measuring the reverberation time or the frequency response of the listening room?

Environmental noise measurement

Can I measure noise by RAL?

How can I measure noise by EA (Environmental noise Analyzer)?

Is it possible to measure noise that was recorded by DAT in the field?

In RAE, is it possible to calculate the noise level of complex noise?

Can RAE be used for evaluating the footstep noise or impact noise in the apartment?

I tried to analyze a low frequency noise by the 1/3 octave analyzer. But the level (dB) is displayed as a minus value. How does it display the absolute sound level?

Electronic measurement

Can I use the oscilloscope to test currents on small electronic systems?

Is it possible to input external electronic signal?

Can I use a probe with USB interface?

Can oscilloscope be used for check of car's ignition system or sensor?

Others

I'm a dentist. I want to measure change in voice quality of patients before and after the treatment.

I want to use the software for my child's homework. I want to measure tone height or wavelength of voice of several birds and insects using the oscilloscope.

Is it possible to estimate the location of the sound source, like a tool for finding the epicenter of the earthquake?

Contents

Category: Measurement tips

How can I make a waterfall plot of a wave file?

Could it be possible to measure the reverberation time from a recorded impulse signal of a room exited with, for example, a pistol shot?

Is it possible to transfer data recorded in the magnetic tape into the analysis software?

Give me advice how to use this software.

How can I analyze an existing sound file (wav format) by RAL?

Is it possible to measure the line-input and the microphone input simultaneously?

The impulse response measurement does not work. Please give me some advice.

My question is how to adjust positions of each unit in the 3 way speaker system. What measurement is suited for this purpose?

Can I compensate a PC's internal noise and a frequency response of microphone?

Which version of software is suited for measuring the time change in the reproduction level of sound data (AVI or WAV format) recorded by the digital video?

Measurement of the wav file and calculation of Leq.

I cannot find a way to load a raw data (.dat or .txt) into Realtime Analyzer and analyze them using 1/3 octave features. Is it possible to use RA in this manner?

Contents

Category: User support and documents

Do you have a user support service when I have some trouble?

Do you have a brochure or a manual of the software?

Do you have literature concerning this software?

Contents


Can I control the window position or start measurements by external commands or keyboard shortcut in RAL? I want following operations.
  1. Open the signal generator.
  2. Start the signal.
  3. Minimize the signal generator window.
  4. Open the oscilloscope.
  5. Start the measurement.
  6. Move the oscilloscope to the right bottom of the desktop.
RAL could not be operated by the external commands. But some operation can be controlled by the keyboard shortcuts. For your purpose, the following operations are available.
  1. Open the signal generator: Alt+S
  2. Start the signal: Alt+S
  3.  
  4. Open the oscilloscope: Alt+O
  5. Start the measurement: Alt+ S
  [Back] [Up]

In Realtime Analyzer, can I save and load parameter settings instantly for future measurements?
All the settings of RA (measurement parameters and window positions) can be saved as "Preset" and can be recalled later. Once you save a Preset during a measurement, you can restart the measurement with exactly same conditions. This function is very useful for shortening the preparation time and for reducing the mistakes in the measurement. If you are using the software in a group, settings for each user can be managed separately. 
  [Back] [Up]

I want to measure the performance of my handmade audio amplifier. Which version of the software is suited for this purpose? In particular, I want to input the sinusoidal wave to the amplifier, measure the output of the amplifier, and compare it with the input waveform to know how much the signal is distorted. 
Distortion of the equipments can be measured by comparing the input and output waveform by the oscilloscope or using the THD (Total Harmonic Distortion) analyzer. The oscilloscope and the signal generator are available in DSSF3 Light, but THD analyzer is available in the higher versions. DSSF3 Realtime Analyzer is highly recommended for this kind of measurement.

Measurement procedures are explained below.

1) Using the oscilloscope

When the input and the output signals are to be compared by the 2ch mode, connect the Left channel of the soundcard's output directly to the Left channel input of the sound card (for measuring the signal generator's output), connect the Right channel output to the amplifier (for feeding the signal generator's output to the amplifier), and connect the amplifier's output to the Right channel input of the sound card (for measuring the amplifier's output). Then, start the signal generator and the oscilloscope. You can see two waveforms (one is the input signal, and another is the output of the amplifier) on the oscilloscope screen at the same time. By changing two inputs of the soundcard, any signals can be compared similarly.

In DSSF3, the screen resolution of the waveform display is much improved (x16 over sampling). So the smooth waveform can be observed up to high frequencies. Attention should be paid when the RA series (RAL, RAD, RAE) is used for measuring the signals above 4 kHz. 

See this application note for the measurement setup. 

2) Using the THD analyzer

THD analyzer can measure the distortion of the amplifier very effectively. In this case, connect the soundcard's output to the amplifier, and connect the amplifier's output to the soundcard's input. You don't need to connect the soundcard's output and input directly. THD analyzer compares the input and the output signals automatically and gives the result (distortion). 

See this application note for the measurement setup. 

  [Back] [Up]

I am considering to use your software. Purpose is to measure the reverberation time of a small room and improve its acoustical condition. My requirement to the software is that it can measure the impulse response, calculate the reverberation time, and save results as a CSV format. Please let me know the software which I should purchase. Equipments are, PC: DELL Inspiron8200, interface: TASCAM US-428, loudspeaker: YAMAHA MSP5, and microphone: SHURE SM58. Is there any problem with my equipments? With how much accuracy can I measure?
We recommend DSSF3 Full-system for measuring the reverberation time and other parameters in the room acoustics. Measurement and analysis of the impulse response can be performed very smoothly. First, wav files with resolution of 8, 16, and 32 bit and with any sampling rate can be read in RA (RAD and RAE can read 16 bit file only). If you have the impulse response data measured by other system, they can be analyzed easily. Second, data analysis in SA now includes ISO standard parameters (RT, Clarity, Definition, Center Time, ...) and STI (Speech Transmission Index).

The impulse response is measured by the Realtime Analyzer by using MLS (maximum length sequence) or TSP (time stretched pulse) signals. Measured data is analyzed by the Sound Analyzer to calculate the reverberation time and other acoustical parameters. Measured impulse response can also be saved as wav files. Analysis result in SA can be exported as a csv format. For the detailed instruction, see the impulse response measurement guide in RA's program manual.

As for equipments, a vocal microphone SM58 seems somewhat unsuitable for the measurement. Condenser microphones for music recording or a high quality measurement microphone might be better. The accuracy of the measurement strongly depends on the hardware to be used. We highly recommend the use of high grade soundcards (e.g. wide dynamic range and flat frequency response). Some of our recommendation can be found in Additional devices for sound measurement. Before the measurement, you can test your soundcard by using the THD analyzer (read the application note for how to test).

  [Back] [Up]

Can the spectrum be saved as a numerical data?
In the Realtime Analyzer ver.5 (DSSF3), octave band analysis data can be exported as a csv format. Also, snapshots of the measurement screen can be created by one click. These functions are not supported in RAE / RAD / RAL. 

For saving and printing the measurement screen as picture files, we recommend the image database software, MMLIB. Measurement data and graph images can be easily stored to construct a measurement database.

See the application note: Measurement data management in Realtime Analyzer for more information. 

  [Back] [Up]

In the Realtime analyzer, what length of data can be recorded? I want to record about 10 minutes stereo sound using a Celeron 1GHz PC. Also, can I save a recorded sound as a text file?
Sound recorder stores data temporarily on a RAM memory first. This data is displayed as a waveform and is used for a real time measurement. It will be lost when the Recorder is closed. If you want, you can save this sound to the hard disk as a wav file. Maximum allowable data length depends on the size of the memory and the hard disk. For example, 70 minutes stereo sound with the sampling rate of 44 kHz needs about 600 MB. 

Generally, recordings saved to the RAM memory, is more readily available and more quickly processed than recordings saved to the hard disk. With the faster computers available today, however, the difference between accessing RAM and hard disk is negligible. It will be no problem in treating 10 minutes sound on the Celeron 1GHz PC.

In the recorder there is no way to save sound as a text file. You can use other software that can convert a wav file to a text file and other formats. We heard that several freeware and shareware can do this. 

In the octave band analyzer in RA ver.5.0.3.4 or later, time series of frequency and level data can be exported into a csv file. Impulse response data can be saved as a wav file or a text file. See the following application note for how to use it. Measurement data management in Realtime Analyzer

 
  [Back] [Up]

I want to measure the frequency response of my self build speaker system. Which software is required? Also, do I need any other device, such as a microphone, and a soundcard? My PC is SONY PCV-JX10BP (desktop), OS is Windows XP Home edition, and the built-in sound device is YAMAHA AC-XG WDM Audio. 
For measuring the frequency response of the loudspeaker, we recommend DSSF3 Light. Basic procedure is to feed a test signal to the speaker, pick up its output sound by a microphone, and measure it by the spectrum analyzer and the oscilloscope. See the following application notes to know about the speaker measurement. Audio measurement report

Our software can work with any type of sound card, including PC's built-in sound chip. So you can start the measurement just after installing the software. However, it is important to remember that the quality of the sound device is the most critical part of the measurement system. Important things are: measurable frequency range, wide dynamic range, low internal noise, distortion, and other artifacts. Measurement results are much affected by the performance of the soundcard.

For example, suppose that you measure the frequency response of the speaker system using a low quality sound card, and the result is a severe reduction in the high frequency range. A problem is that it is not clear whether it is a response of the speaker or the sound card. So, we recommend you to check the performance of your PC's sound device before the actual measurement. See the following page for how to check the sound device. Operation guide of the Realtime Analyzer, 2. Adjustment before a measurement

If the performance is not good and if you prefer better one, you can replace the soundcard and microphone. See the following page to know about the additional equipments. Additional devices for sound measurement

  [Back] [Up]

I am trying to use a PCMCIA sound card (RME Hammerfall DSP) with RAD, but it does not work. The sound card does not appears in RA's input / output device selector. What should I do? 

In RAD (also RAL and RAE), sound device can not be selected directly. Sound device is selected in the Windows volume control. Check the control panel > sound and multimedia property > Audio tab. The device should be selected as a "Preferred Device". Audio interface can be used in our software only if the device operates compatibly with Windows' sound mixer.

In DSSF3, the sound device (e.g. built-in soundcards and USB audio interface) can be specified directly in the RA's main window. Different devices can be specified for input and output separately. We have been reported that the USB device (e.g. TASCAM US-122) did not work with RAD, but worked with DSSF3. 

  [Back] [Up]

I installed RAD in several computers. When I measured spectra in these computers while reproducing a "silent" wav file, I got different noise levels. I'm wondering what caused this difference. In this case, the wav file seems to be converted to the analog signal and then converted to the digital signal again by the built-in sound chip before measured by the Realtime Analyzer. Am I right?
RAD can't measure wav file directly, so we guess you reproduced it by Windows media player or something, and measured it by RAD. If so, you are correct. You got different noise levels because the floor noise level is different for each soundcard. It is not a problem in the measurement if you get enough S/N ratio. You may reduce the floor noise if you replace the soundcard or use the external audio interface.

More important thing in the measurement is to reduce distortion. Measured signal would be distorted when the input/output volume is too large. In most cases, the most problematic device is the analog amplifier after the D/A converter. You should adjust volume carefully before measurement. This can be done by measuring the response of the soundcard using pink noise, sine sweep, and the spectrum. See this operation guide for how to adjust before measurement. Distortion of the soundcard can also be measured using the THD analyzer

Using the sound recorder, you can measure the wav files directly. It means you can measure digital signal itself without passing through DA/AD converter. 

  [Back] [Up]

RAD does not work. The following message always appears. What should I do? "Error message: The specified format is not supported or cannot be translated. Use the capabilities function to determine the supported formats."
This message appears when the soundcard or its driver does not work normally. Possible reasons are: driver is broken, driver has not been updated when the OS was updated, or problem of the driver itself. 

Check whether the Windows volume control is working properly. RAD (RAL and RAE too) inputs/outputs signal through the Windows volume control. So, the input/output device (e.g. wave, CD, line) must be able to be selected on the volume control. If those devices don't appear on the volume control, soundcard driver must be reinstalled. After reinstallation of the driver, install the program again.

Another possibility is that the soundcard does not use Windows' sound mixer but use its own sound mixer. In that case, reinstallation of the driver does not solve the problem. Try our latest program, DSSF3. In DSSF3, soundcard can be selected directly. We have been reported from our users that RAL/RAD/RAE does not work with some latest soundcard, but DSSF3 does work. 

  [Back] [Up]

Can I use a probe with USB interface?
We heard that an electronic probe with USB interface is available. But we have not tried it. For how to connect the probe to the PC's microphone input, see the measurement report. "Connection of Oscilloscope Probe" http://www.ymec.com/hp/signal2/probe1.htm.
  [Back] [Up]

Online update failed in the DSSF3. Error message "YMUPDATE.DLL is not found" appears.
It is a problem of the old installer program. Delete the program completely and download the latest installer again.

Before the installation, please remember to backup the DATA folder, in which the measurement data is stored, before the installation. Otherwise, your previous data will be deleted because the installer program overwrite the DATA folder.

After reinstallation, your registration information is left as it was. When the program requires a Registration Number after reinstallation, input the registration number we sent to you before. If this number is refused, please contact us.

  [Back] [Up]

When measuring the impulse response, which range should I read for measuring the phase in each frequency?

When you measure the impulse response, you can find its inverse filter (i.e. reciprocal of the transfer function) by clicking the "Save" button on the impulse response measurement window. Green curve shows the phase spectrum of the system except that the sign is reversed. Phase is shown between -180 and +180 degree. See the operation guide for a step by step instruction. 

If you measure the binaural impulse response and analyze it by the Sound Analyzer, phase delay between two channels input (Left and Right) can be measured using the cross-correlation function (CCF). The maximum peak of the CCF indicates the phase delay and corresponds to the angle of incidence of sound. In the audio systems, it is important that the sound comes from a center position. This can also be checked simply by using the Correlation meter of the Realtime Analyzer. See this application note. Speaker phase check

Phase meter has been added to the FFT analyzer in DSSF3. This meter displays the phase difference between two channels as a function of frequency. To test the phase delay of the audio equipments, input the *monaural* pink noise as a test signal, and measure the two outputs to be tested by the phase meter. See this Q&A too. 

  [Back] [Up]

In the THD analyzer can I acquire the numerical data?
No. It only displays the result at the present. Output of a numerical data is now under development. Please use Windows' ScreenCopy function, or MMLIB to save the measurement data as a picture file. See the following application for more instruction. 

Measurement data management in Realtime Analyzer

  [Back] [Up]

Can the measurement results of RA (spectrum, octave analysis, and so) or SA be exported to other software (Excel)? Now I use PrintScreen to copy the window image.
Results of the impulse response and the running ACF by SA can be saved as a CSV format. Measured impulse response can be saved as a wav format or a txt format. 

As for RA's FFT analyzer, data export function is available in the octave band analyzer. Time series of frequency and level data can be recorded at a specified interval (minimum is 1 s) and saved as a CSV format. 

For other measurement, please use PrintScreen function.

1) open the measurement window
2) press Alt + PrtScr keys of the keyboard
at this point, the screen image is saved into Windows' clipboard
3) paste it to other software (e.g. MS paint, MS word) by pressing Ctrl+V keys
4) save the image into files

MMLIB is also a convenient tool to manage measurement data as picture files. See the following application for more instruction. Measurement data management in Realtime Analyzer

  [Back] [Up]

I want to try visualizing and classifying some "metallic sound". I have three questions.
1) Which software is the best for this kind of measurement? Particularly I am planning to perform a frequency analysis.
2) I own a digital video camera, a microphone, and a sound level meter. Do I need other specific devices?
3) Can the recorded sound by the digital video be analyzed later?
1) We recommend DSSF3 Full-system version for your purpose, because this version includes Sound Analyzer. Using the running ACF/CCF analysis, tonal quality of sound can be investigated at a high temporal resolution.

If you are planning to perform only a real-time measurement, DSSF3 Light would be sufficient. Especially, power spectrum, octave band analysis, and spectrogram can help visualizing sound.

2) You need a microphone amplifier and a sound interface. See the following pages.
http://www.ymec.com/hp/signal2/tool1.htm
http://www.ymec.com/manual/install/equipment_en.htm.

3) Digitally recorded sound can be analyzed, but it is important to use the recorder that is equipped with a manual recording level adjustment. It is also important to record a reference signal for calibrating the sound pressure level. See the following link for how to use a digital video for the sound measurement.  http://www.ymec.com/hp/signal2/basic3.htm.

  [Back] [Up]

I want to compare the frequency characteristic of the sound level of different systems from the impulse response data measured by RA. I know this can be done by SA, but I want to calculate it using MATLAB. For this purpose, I want a "raw" impulse response data as a .wav format. In RA, data can be outputted, but it is normalized between -1 and +1. It is not good for comparing the sound level. Can I get a wav format impulse response data which is not normalized?
Only the normalized impulse response is available at the current version of RA. This problem might be revised in the future update. At present, you can use the following method for comparing the sound levels.

1) Measure the impulse response using MLS signal.

2) Output wave file as "Input signal". This is a recorded raw data during a measurement without normalization. You can calculate the sound level from this signal.

  [Back] [Up]

When I measured the impulse response (input device was set to Mixer), obtained data was so noisy. When I try the adjustment function, input and output level is OK but measuring time is always NG. S/N ratio is about 22 dB. What is the problem? I use RAE in a Pentium4 (2.4GHz) PC with Windows2000. Soundboard is ONKYO SE-80PCI. 

According to your web site, I set the Windows audio properties (Hardware acceleration: None, and Sample rate conversion quality: Best), but it did not work. When I tried the same measurement by another old PC with SoundBlaster DigitalAudio II, clean impulse response was obtained. So, is a problem in a ONKYO's soundboard ? I thought that it is a high level soundboard, so I am puzzled. Please give me some advice. 

It seems that the microphone input level is good. One possible reason is the distortion at the analog amplifier after the D/A converter of the soundcard. As you can see in this application note, you can adjust input/output volumes to reduce distortion. 

In the impulse response measurement, a test signal is generated at 70 % digital level. Your soundcard should not cause distortion at this digital volume. Input volume can be adjusted in the main window of the Realtime Analyzer. Output volume can be adjusted in the Windows' volume control. 

If the distortion still exists after the adjustment, try to measure the impulse response by using TSP method with Auto Level and Auto Retry off. In comparison with the MLS method, clean impulse response can be measured easily.

Another solution is to use another soundcard. We recommend USB sound interface, such as EDIROL UA-5. This device is easy to use and has a good performance. Also, the use of the external microphone amplifier with a PC's line-in connector may solve the problem. If you have another PC, try the same measurement so that you can compare the results. This helps to find the cause of the problem.

  [Back] [Up]

I checked a frequency characteristics (spectrum) of the impulse response by SA. Also I output the same impulse response data from RA as a .wav format and calculated a spectrum by MATLAB. Problem is that these two spectra are different. I assume that this is because the impulse response is normalized in RA. If so, can I get a impulse response data before the normalization?
Normalization of data does not change the spectrum. It is assumed that the data size of FFT is one possible reason in your problem. In SA, spectrum is calculated for the whole data length. Check the calculation condition in MATLAB.
  [Back] [Up]

In the spectrum view of the FFT analyzer, "Peak Hold" check box cannot be checked. Is this a specification of RAL? I want to draw a graph of the frequency characteristics using a sweep signal. What can I do?
RAL does not have a peak hold function in the spectrum. Peak hold is available only in the 1/3 octave band analyzer. Try DSSF3 Light, in which peak hold is available in both the spectrum and the octave band analysis. 

See the following application note for a detailed instruction of how to measure frequency response using a sweep signal. Sweep generator

  [Back] [Up]

I want to analyze a snore sound. I also need a realtime analyzer (time / energy / frequency analysis). Which version of software is suited for this purpose?
In DSSF3 Light, real-time analysis using the spectrum, octave band analysis, and spectrogram (sonogram) is available. Some of these functions are also available in RAL, but DSSF3 Light is equipped with much improved functions. A wav format sound file can be measured directly. Snapshot of the measurement window can be saved as a picture file, and the numerical data of the octave band analysis can be saved as a csv format.

By using the running ACF measurement, the fundamental frequency and the formant frequency can be analyzed as well as the speech analysis. If you would perform this analysis, DSSF3 Full-system is required. 

If you want to monitor snoring sound or any other noise while you are sleeping, Environmental noise Analyzer would be very useful. This module (available in DSSF3 Environmental noise) can record the sound automatically only when the sound level exceeds the specified trigger level. 

  [Back] [Up]

What is the difference of DSSF3 and RAE?
Previous version of the DSSF3 (ver.3) has been released as RA series in 2002. Basically, RA series (RAL, RAD, RAE) and DSSF3 have the same programs, but some of the advanced functions available only in DSSF3. See the function list to compare the functions available and DSSF3 news for the upgrade information. The latest OS, PC, soundboard, or USB interface may not work with RA series, because no future upgrade is scheduled. In that case, try DSSF3.
  [Back] [Up]

How can I measure noise by EA (Environmental noise Analyzer)? 

See operation guide of EA program manual for the step by step instruction of noise measurement by EA. 

  [Back] [Up]

I want to use software in other PC. How can I do it?
Install the software in the PC you want to use. Please remember that one license of the program is valid for one computer. If you want to use the program in two or more computers, please purchase additional licenses.
  [Back] [Up]

In the current version of RA or EA, input volume is controlled by the slider. If this volume is changed, input level changes and so the precise measurement could not be performed. What can I do? I think that the input volume should be controlled by numerical values or stepwise volume. Then even when the input volume is changed during the measurement, it could be re-adjusted easily.
Input volume control of RA and EA is interlocked with the Windows volume control. Controlling the input volume by the slider is a configuration of Windows. 

However, it is no problem in the actual measurement. Once the input level is adjusted and saved in the calibration window, input volume is re-adjusted automatically when the calibration data is selected. See the operation guide for how to use this function. 

  [Back] [Up]

Why only the display of an input of a peak level monitor can be changed between ON and OFF?
It is for monitoring the input level only when required. When you don't monitor the input level from the input device, it can be set OFF.  In DSSF3, the peak level monitor is always ON. 
  [Back] [Up]

Show me a block diagram of software and sound devices in the computer. I want to know how the input/output device, such as microphone and line-in, is connected to the software. 
Below is the block diagram, which shows the relationship between the Realtime Analyzer and the soundcard's input/output device. Available input device is displayed and can be specified in the Realtime Analyzer. In this figure, Line-in is selected. This device selection is interlocked with the Windows' recording control. Output device is WAVE/DirectSound (device name depends on the soundcard used). Other devices have to be muted in the Windows' volume control to prevent howling.


There are three volume controls in the Realtime Analyzer. The first one, "Input Volume" is accessed from the main window of the Realtime Analyzer. This volume is interlocked with the Window's recording control panel, and adjusts the input signal level before A/D converted. The second is the output volume, that is controlled by the signal generator's "Output Level". This volume is interlocked with the Window's volume control panel, and adjusts the level of the D/A converted signal. 

Third is the "Digital Output" on the signal generator. This is an original function of the Realtime Analyzer, that controls the amplitude of the digital signal (wave data) outputted from the signal generator. 

  [Back] [Up]

Can DSSF3 measure the phase spectrum or the group delay?
In DSSF3, the phase difference between two channels can be measured by the phase meter in the FFT analyzer. In this meter, the phase difference between two channels is displayed as a function of the frequency. 

A procedure for the measurement of amplifier's phase characteristic is briefly described below.

1) Connect the left channel of the soundcard output to the left channel of the soundcard input directly. This becomes the reference.

2) Connect the right channel of the output to the amplifier's input, and connect the amplifier's output to the right channel of the soundcard input.

3) Generate a *monaural* pink noise as a test signal on the signal generator.

4) Start the phase meter from the FFT analyzer. The phase difference in each frequency is displayed. This is the phase delay of the amplifier.

Note!: Phase meter is available only in DSSF3. See the function list to check the available functions in your version of software.

Phase spectrum can also be obtained in the impulse response measurement. When you measure the impulse response of your system, setup the inverse filter by clicking the "Save" button on the impulse response measurement window. You can see the inverse filter of the system. Green curve shows the phase spectrum of the system except that the sign is reversed.

See the measurement report below for how to measure the impulses response.
Audio measurement report 2 http://www.ymec.com/hp/signal2/audio2.htm
Audio measurement report 3 http://www.ymec.com/hp/signal2/audio3.htm

  [Back] [Up]

I use RAL for setting up a self-built car audio system. First, I set a crossover and a time alignment. Then I set the equalizer to almost flat by using the 1/3 octave analysis and pink noise CD. But unfortunately, when I listened to a music CD, low frequency was too emphasized and midrange was unsatisfactory. I set the equalizer flat based on the 1kHz response. Frequency response is almost flat, but sound is horrible. What was wrong? Should I set the equalizer by using a music CD, or was my adjustment procedure was wrong? Please give me an advice.
You should know the frequency response of a microphone and PC before the measurement. This is a very important check for obtaining a correct response of an audio system. If your measurement system has a problem in the frequency response, it can be compensated. See the program manual of RA for how to do this. 

After correcting the microphone's response, you can start adjusting the equalizer using the pink noise and 1/3 octave analyzer. Note that too low and too high frequency range can not be equalized perfectly. It is important not to boost the low frequency range. Keep in mind that between 200 and 1000 Hz should be flat. Between 2000 and 4000 Hz should be lower around 3-6 dB, because human ears are sensitive to these frequencies.

  [Back] [Up]

Do you have a low price software equipped with a distortion analyzer?
DSSF3 Realtime Analyzer and higher versions have a total harmonic distortion (THD) analyzer. See this application note for how to use the THD analyzer.
  [Back] [Up]

I want to measure a car audio system by using RAL. I have two PCs. One is an old notebook with Windows 95, and another is a desktop with Windows 98. To measure inside a car, I want to use a notebook. But my notebook cannot support a simultaneous input and output. So I can't use the signal generator and the realtime analyzer at the same time. If I use a test CD (pink noise or tone) for the measurement, is it OK that only input is available in my soundboard? Also, when using a soundboard of an old PC, is the input signal affected by the frequency characteristics of the A/D converter?
As for the test signal, it is OK if you can output sound from a CD player. 

As for the performance of the A/D converter, you need to measure it before measurement. This is a very important test to obtain accurate measurement result.

You will see how to do it in this application note: Measurement of PC's soundboard by RA. Connect a CD player's output to a PC's line-in connector. 1/3 octave band analysis for a pink noise tells a frequency response of the PC's sound circuit. Oscilloscope display for a 1kHz tone tells about a distortion of the sound circuit.

  [Back] [Up]

I have a question about a measurement of my 3-way speaker system. It consists of 38 cm woofer (cone), squawker (horn), and tweeter (horn). Crossover is 600 Hz and 8 kHz, and 6dB/oct channel divider is used. Woofer is set in the speaker box, and squawker and tweeter are put on the box. Position of squawker and tweeter can be easily changed back and forth. My question is how to adjust a position of each unit strictly. What measurement is suited for this purpose?
Impulse response measurement is good for adjusting the position of speaker unit. Measure the impulse response for three units separately at the listening position. Check the time delay of the direct sound for three units. Then move units so that the time delay becomes equal. 

See the measurement report http://www.ymec.com/hp/signal2/audio2.htm for how to measure the impulse response.

  [Back] [Up]

Can RAL be used for the adjustment of time alignment of loudspeaker? Now I measure the distance of speakers from the listening point and adjust the position. But after all, I cannot but depend on a listening test. So I want to measure the difference of arrival time of sound from left and right speakers to adjust the position of loudspeakers correctly.
As for the localization of sound in a listening room, interaural time difference (ITD) is the important parameter. This is a time difference between left and right ear input. When the ITD is zero, the sound is heard as if it comes from the center position. ITD can be measured in real-time by the cross-correlation function. Feed a pink noise to the both speakers at a same level and place the two microphones at a listening position. 

Time alignment of each unit of a multi-way speaker system can be adjusted using the impulse response. Impulse responses are measured for each unit at the listening position. The distance between the unit and the listening position is calculated from the time lag of the onsets of each unit response. To compensate time lag, each unit position is adjusted. 

  [Back] [Up]

Can oscilloscope be used for check of car's ignition system or sensor?
As you can see in http://www.ymec.com/hp/signal2/probe1.htm, oscilloscope can be used to measure the signal other than sound. The electronic probe with the AC output or the RS232C serial interface can be used for this purpose. Recently, the electronic probe with USB interface is also available. 
  [Back] [Up]

In the Environmental noise analyzer, the sound pressure level (SPL) is displayed in minus value. How can I change this to display the absolute sound level?
In a default setting, SPL is displayed as a relative level. The maximum input level is set to 0 dB. To display the absolute sound level, you need to calibrate your microphone by using a sound level meter or a calibrator. For how to calibrate a microphone, see the program manual of RA.
  [Back] [Up]

I want to measure the reverberation time and the frequency response of the listening room. Can DSSF3 be used for this purpose? Also, are there any required equipments for this purpose?
Yes. The reverberation time, transfer function (frequency response), and other room acoustics parameters can be measured by DSSF3, using the impulse response function. As a simpler measurement, the frequency response can be measured by the spectrum analyzer using a sine sweep or a pink noise as a test signal. This measurement is possible by RAL. 

In addition to the PC and the software, you need a microphone, amplifier, and soundcard for the measurement. See this page for information about the additional equipments.

  [Back] [Up]

Tell me the difference between "microphone" and "line in" for the input device setting. It seems that the input level and the spectrum are different between these settings.
The output voltage of a microphone is small and does not reach the required voltage of the soundcard. So, when a sound from a microphone is measured, its amplitude has to be amplified in some way. 

When the "microphone" is selected as the input device, the input signal to the mic-in terminal is amplified by the built-in microphone amplifier and then converted to the digital signal. Generally, built-in microphone amplifier does not have a good performance for sound measurement (i.e. poor frequency response and high floor noise level). So we recommend using the "line-in" connector in the measurement.

When the line-in is selected, built-in microphone amplifier is not used. It means that the input signal itself will be measured. Line-in is supposed to be used to import signals from the audio equipments having the internal amplifier, such as CD player, MD player, and DAT player. So, an external amplifier is required when the line-in is used to input the microphone signal. For example, microphone amplifier, audio mixer, or portable DAT recorder can be used. 

If your PC does not have the line-in connector, PCMCIA or USB type audio devices are highly recommended. These devices have a high quality microphone amplifier and line-in connector. Using such a device, your PC turns into a high grade measurement equipment. More information can be found at Additional devices for sound measurement.

  [Back] [Up]

Can I compensate a PC's internal noise and a frequency response of microphone?
Internal noise of the soundcard can't be compensated. You may reduce the internal noise by replacing the soundcard or using the external audio interface. But generally, it is not a problem if you can get enough S/N ratio. 

More important thing in the measurement is to reduce distortion. Measured signal would be distorted when the input/output volume is too large. You should adjust volume carefully before measurement. This can be done by measuring the response of the soundcard using sine sweep and the spectrum. See this operation guide for how to adjust before measurement. Distortion of the soundcard can also be measured using the THD analyzer

Microphone's frequency response can be compensated if you have its response data. Realtime Analyzer has a calibration function in which you can edit the frequency response curve for compensating the microphone's response. See the operation guide for how to do it.

  [Back] [Up]

I want to measure the time change in the reproduction level of sound data (AVI or WAV format) recorded by the digital video. Frequency characteristics of sound will also be measured with the A-weighting filter. Which version of software is suited for this kind of measurement?
We recommend DSSF3 Light. Power spectrum and octave band analysis can be used for measuring the frequency characteristics of sound, including A- and C-weighting filter. For measuring the time change of sound level, do the octave band analysis with a small interval (minimum is 1 second). Measured data can be exported as a csv file. 

If you need finer time resolution of the level data (i.e. order of 0.1 or 0.01 second), Running ACF measurement is available. This measurement is available in RAD and DSSF3 Full-system. 

  [Back] [Up]

I am using RAL, but I want to version up to RAE. What should I do? 
You can upgrade to the higher version of the program by paying the difference. Please  let us know your request.
  [Back] [Up]

I installed the program and used it during a trial period, and I decided to buy it. However I will change my OS and disk partition. (A hardware is exactly same.) Is there any problem with it?
If you format the hard disk, you need to reinstall the software.
  [Back] [Up]

I want to download the RAL to one PC and then install it in two or more PCs. When I did this before, the program did not operate normally. My OS is Windows 98 for both PCs. Could you give me some advice?
Even if you copy the program EXE file (e.g. PcAudioLT.exe for RAL), it does not operate on the other PC. You must install the program properly. After downloading the installer program, copy this file (self-extracting file) to a PC, in which you want to install RAL, through a floppy disk, CD-ROM, or LAN. Then start the installer. Note that one license of the program is valid for one PC. If you want to use the program in two or more PCs, please purchase additional licenses.
  [Back] [Up]

I will format my hard disk and reinstall the program. However I want to use previous data again after reinstallation. Show me how to back up my data.
Data are saved in the directory:
C: \ Program Files  \ RAEE  \ DATA

<*>

Save all files in this folder. Then format your disk.

After you install the program, put the saved file in the same directory. You can use the previous data on new environment.

<*> If your software is RAD, this folder name is "RAD". Like this, folder name here is product name. 

Also see the Install guide for more information. 

  [Back] [Up]

How can I re-install the program? I copied the all files within program folder, but it did not work. 
Installation of the program can't be done by copying the program files. Please download the installer again or copy the installer to the new PC and run the installer. Even if the software is reinstalled, your user registration is still remained.
  [Back] [Up]

What can I do to use the program after formatting the hard disk?
Please download the installer from the website and install the program again. You need to register again when the hard disk is reformatted or replaced. In such a case, please mail us.
  [Back] [Up]

I want to have a software in a CD-ROM because I often format the hard disk. How can I do it?
We are sorry, but shipping of the software CD-ROM outside Japan is out of service. You can make a software CD if you have a CDR drive. Copy the installer file to the CDR. Note that you need a new registration number after formatting the hard disk.
  [Back] [Up]

I have purchased your software, but I haven't received it.
Please note that we are not delivering the software itself, but providing the license. To receive the software, download the installer from the products web site and install the software. Then, let us know the hard key to receive the registration number. Registration procedure is summarized in Hard key and User registration
  [Back] [Up]

I want to upgrade from RAL to RAD. Should I uninstall RAL before install RAD? 
It is better to uninstall RAL. RAL and RAD does not work at the same time. It is no problem because all functions of RAL are available in RAD. 
  [Back] [Up]

How can I update the program when I cannot connect to the Internet?
Update of the program is available only via online update. If you cannot connect to the Internet, download the latest installer file on the other PC, copy it to the PC to be used, then re-install the program. In this case, you need not register the program again because the hard key has not been changed. However, note that the previous measurement data would be overwritten by the new files. So, don't forget to backup the measurement data. See the install guide for how to backup data. 
  [Back] [Up]

How much does it cost for the online update?
Online update of the DSSF3 is available for free. When the new major upgrade of the program will be released, the current version would not be updated online  any more. 
  [Back] [Up]

Is the online update available during the trial period?
Yes, online update is available anytime.
  [Back] [Up]

Can I receive an invoice or an official purchase order? 
Please contact us.
  [Back] [Up]

Is the hard key changed if I uninstall the program or reinstall OS or format hard disk? 
"Hard key" is a number that is created when you install the program. This number is inherent on each computer. Entering a "registration number" corresponding to the hard key releases the protection, and enables you to use the program after a trial period. Unless you reformat hard disk, the registration information (hard key and registration number) remains valid even though the program is uninstalled or OS is reinstalled.

However, if you format the hard disk, the registration will become invalid. A new registration number will be required, because the new hard key is created when you reinstall the program again. 

2 [Back] [Up]

You say on your website that "One license of the program is valid for one computer". Do I need to purchase a license again or do I have to pay a kind of re-registration fee, when the software is reinstalled or moved to another computer?

In such a case, we will provide a new registration number for special fee. Please let us know your name and your new hard key, and a reason you need a new registration. After checking your order information, we will inform you a new registration number. See the following page for how to find a hard key. http://www.ymec.com/store/en/register.htm

  [Back] [Up]

Do you have a user support service when I have some trouble? 
We have a user support by email. Please mail us for any question, trouble, bug report, and so. We will reply you as soon as possible. When some problem is found in the program, we will fix it soon. You will get the latest version by the online-update. 
  [Back] [Up]

What is the hardware and software requirement?
DSSF3 and RA series (RAL, RAD, and RAE) works properly on the standard PC with the soundcard, and Microsoft Windows 98, Me, 2000, or NT4. System requirements are summarized in the table below, but it is no problem if it works on your computer. Do the operation check before purchasing the software.
CPU Pentium II 266MHz or faster
RAM 128 MB or more
HDD 10 MB or more
OS Windows 95/98/ME/2000/NT4.0
Display 1024x768 High Color
Sound card Windows compatible full-duplex soundcard is required.
  [Back] [Up]

What is the lowest frequency which can be measured in the "Spectrum"?
The lowest frequency is determined as Sampling rate / FFT size. For example, when the sampling rate is 48000 Hz and the FFT size is 4096, the lowest frequency is 11.7 Hz. You can measure lower frequencies by increasing the FFT size or decreasing the sampling rate. But note that the lower limit of the spectrum display is 1 Hz. 

Also keep in mind that the measurable frequency will be affected by the performance of audio device and sound card. Generally, the audio device can measure signals in the audible frequency range of between 20 Hz and 20000 Hz. So, lower frequencies below 20 Hz will be much attenuated.

  [Back] [Up]

I want to measure the noise level (dBA) of the recorded sound files. Also I want to record the frequency analysis data and calculate the statistical noise metrics such as Leq (equivalent level) or Lx (percentile level). How can I do them in EA?
In DSSF3 ver.5, measurement of the sound file (wav file) is available by using sound recorder, and the data can be exported as a CSV format from the octave band analyzer. By these function, the procedure described below becomes very easy. Also, a sample Excel macro for calculating Leq, Lx, and other noise criteria from the octave analysis data is available here
  • Measurement of the noise level from the wav file.

The sound file (WAV format) can't be read directly in RAL/RAD/RAE. Use the sound player (e.g. Windows Media Player) to play sound and measure it by the FFT analyzer. In RAD, RAE, or DSSF3, wav file can be read and measured directly. See the program manuals of RA's running ACF measurement. Same measurement can be more easily performed in EA (Environmental noise Analyzer) ver.5.). See the EA's program manual.

For measuring the noise level, set the calculation conditions as follows. If you measure in RA, these settings should be done when the sound is analyzed later in SA (Sound Analyzer). 

1) Integration time: Set as 0.5 s to measure the noise level to emulate the sound level meter's FAST setting.

2) Running step: This is the calculation interval of the noise level. Set as 0.1 s. 

3) Weighting: Select the A-weighting to measure the level in dBA.

4) Max delay time: This parameter will not affect the calculation of the noise level. Set the short time (e.g. 0.01 s) to decrease the calculation load. (To analyze sound in more detail, this should be long enough (half of the integration time) to capture the lower frequency of sound.) 

  • Calculation of Leq from the measured noise level.

The Leq is defined as "the steady sound level over a specified period of time that would produce the same energy equivalence as the fluctuating sound level". It means the averaged noise level measured for the time varying noise, and the SPL values that EA and SA calculate for every calculation step is exactly the Leq as shown in the following equation. The integration time T is the parameter that is specified in the calculation condition.

Calculating the Leq for longer period of time (e.g. 60 s), however, takes long calculation time and is not a convenient way. So the practical way to calculate the long time Leq is averaging the short time noise levels. To take an average, the noise levels measured in dB is first converted to the real values, averaged, and then converted back to dB again. This calculation is not available in the current version of DSSF3. So the calculation should be done in other software (e.g. MS Excel). To do so, measured data can be saved as CSV or TXT format. See the following instructions for how to do it.

1) Open the noise data measured by RA or EA. 

Measured data can be open by SA. If the noise was measured by EA, sound level has already been calculated. But it was measured by RA, calculation is now needed. Set the conditions above and start the calculation. For more information of SA, see the program manual

2) Data export.

 Select the "Output Files" from the "Parameter" menu on the main window of SA. Name the data and save as a CSV format.

From now, calculation is done in Excel.

3) Open the CSV file.

The data is shown as below. Use only the SPL values for the calculation.

----------------------------------------------------------------------

[Factor1]

Time [sec] 0 1 2 3 4 5

Phi-0 [dB] -41.28 -47.03 -44.04 -45.85 -42.28 -39.18

Tau-e [ms] 3.41 6.64 38.65 2.98 6.74 42.75

Tau-1 [ms] 1.69 1.94 2.25 2.13 3.69 1.75

Phi-1 0.06 0.18 0.15 0.09 0.16 0.41

SPL [dB] -42.79 -47.33 -44.8 -46.65 -43.74 -41.21  <- Use only this line

IACC 0.41 0.89 0.55 0.37 0.46 0.32

TauIACC [ms] 0.19 0 0 0 0 0

WIACC [ms] 0.12 0.24 0.13 0.12 0.1 0.1

----------------------------------------------------------------------

8)Convert the SPL values (dB) to real values. Use the equation P = 10^(dB/10). 

9) Calculate the average for all values. Then convert to the dB again by dB=10*log10(P). The result is the Leq for a measured period. 

  [Back] [Up]

What is the frequency range of the oscilloscope?
The lower limit of the oscilloscope is mainly determined by the CPU power. For displaying a low frequency signal, "Sweep Time Range" should be set to large. For example, to see one cycle of 1 Hz tone, Sweep Time Range has to be larger than 100ms/div. However, the calculation load becomes high at such a condition. It might be difficult to display a signal smoothly if you use a slow PC.

Also keep in mind that the measurable frequency will be affected by the performance of audio device and sound card. Generally, the audio device can measure signals in the audible frequency range of between 20 Hz and 20000 Hz. So, lower frequencies below 20 Hz will be much attenuated.

The upper limit is half of the sampling frequency. When the sampling frequency is set to 48 kHz, the upper limit becomes to 24 kHz. But note that the actual performance depends on the quality of the soundcard used.

  [Back] [Up]

What is the unit of the Level Range in the oscilloscope? 
Basically, an oscilloscope displays a signal waveform with the vertical axis representing voltage and the horizontal axis time. In the digital oscilloscope (software), input signal is also a voltage, but it is digitized by the analog-to-digital (A/D) converter. In the Realtime Analyzer's oscilloscope, the signal amplitude is represented by an integer between 1-32768. 

Level Range decides a value of one grid of the vertical axis in the oscilloscope display. For example, when the Level Range is set to 1, one grid becomes 1. When the Level Range is set to 32768, one grid becomes 32768. Usually, this value is set automatically so that the signal is displayed in an appropriate range. 

If you want to measure the absolute voltage values, the input signal level can be calibrated by using the voltmeter. See the following application notes for how to do this. 

http://www.ymec.com/hp/signal2/probe2.htm

http://www.ymec.com/hp/signal2/probe3.htm

  [Back] [Up]

What is the difference of 1ch and 2ch in the impulse response measurement? 
The 1ch is for the monaural measurement and the 2ch is for the binaural (stereo)  measurement. The 1ch measurement is sufficient to measure the monaural criteria, such as the reverberation time or the sound pressure level. But to measure the spatial properties of the sound field, it is common to measure the impulse response by using the binaural microphones (dummy head or real head). For more information, see the appendix of SA's program manual.
  [Back] [Up]

I want to attach the sound waveform taken by the oscilloscope on a document such as MS Word. 
Copy a window using Window's screen copy function (Alt + PrintScreen keys), and paste it to a MS Word document.

Graph area can be enlarged by double-clicking the window title or clicking the maximize button in the upper right corner of the window. 

Click the reload button of your browser. You can see how the measurement window changes to an expanded graph.

* In this expanded graph mode, you can only start or stop the measurement with the Alt + S keys, although other buttons are not available.

  [Back] [Up]

In Realtime Analyzer, can the measured data by such as the spectrum and the octave band analysis be printed? 
For printing the measurement screen, use Windows' screen copy function. Press alt+PrtScr to copy a picture to a clipboard, then paste to other software (e.g. Microsoft Paint, Word, etc). 

For saving and printing the measurement screen as picture files, we recommend the image database software, MMLIB. Measurement data and graph images can be easily stored to construct a measurement database.

In the Realtime Analyzer ver.5 (DSSF3), octave band analysis data can be exported as a csv format. Also, snapshots of the measurement screen can be created by one click. See the following application for more instruction. 

Measurement data management in Realtime Analyzer

  [Back] [Up]

Is it possible to export the 3D graph of the FFT analyzer to the other software (e.g. MS-Excel)? 
It is not possible to export the 3D graph directly, but the frequency analysis data by the octave band analyzer can be exported as a CSV format. Time series of frequency and level data is available. Using this data, similar 3D graph can be created. The frequency resolution of 1/1, 1/3, 1/6, 1/12, and 1/24 octave is available. The data export function is only available in DSSF3. See the following application for more instruction. 

Measurement data management in Realtime Analyzer

  [Back] [Up]

I'm a newbie in the audio measurement. I can't connect PC with the audio equipment. What equipments do I need for audio measurement?
At first, you need an audio cable to connect the PC and audio amplifier for reproducing  sound by a loudspeaker. In many cases, a stereo mini jack cable can be used to connect computer's "headphone out" to the amplifier. 

Second, a microphone is required for measuring sound. A microphone is connected to the "Mic in" connection of the computer. 

Third, you may need an external audio interface, because the input/output device of standard PCs are generally poor, that is not suitable for the audio measurement. You can find a lot of devices with PCMCIA and USB interface. 

You can find more information about the necessary equipments in this page. Additional devices for sound measurement

  [Back] [Up]

Can I perform a measurement using the built-in microphone of PC? Or should I use additional equipments? 
Simple test can be performed by the built-in microphone. But generally the performance of built-in microphone is poor. It may be difficult to obtain a correct results. We recommend you to use the external microphone, amplifier, and sound device (USB or PCMCIA interface). 

You can find more information about necessary equipments in this page. Additional devices for sound measurement

  [Back] [Up]

I installed Roland EDIROL (UA-5) as a USB sound device. But when I start RAL, a message "can't use mixer" appears and it does not work. What should I do?
When you use a USB device, keep in mind the following procedures.
  1. Connect a device to PC.
  2. Plug in the power to the device and turn it on.
  3. Start RAL.
  [Back] [Up]

Should I use the microphone amplifier for the measurement?
You can use a microphone with the Mic-in port of the computer. But for a precise measurement, external microphone amplifier is recommended.  PC's Mic-in circuit is generally poor in performance (e.g.. noise, distortion, limited frequency range). For example, suppose that you measure the frequency response of the speaker system using a low quality sound card. You get a result that shows a severe reduction in the high frequency range. A problem is that it is not clear whether it is a response of the speaker or the sound card. To get a precise results, we recommend to use a high grade audio interface in the sound measurement.

You can find more information about the necessary equipments in this page. Additional devices for sound measurement 

  [Back] [Up]

What kind of microphone is recommended for the sound measurement? I want to measure the frequency characteristics and the sound pressure level in a listening room.
Precision of the sound measurement is greatly influenced by the quality of microphones. The frequency response of the microphone is important when measuring the frequency characteristics of a room or an audio components. 

 It is recommended to use microphones that are being sold as "calibrated", or "measurement" microphones. Such microphones are usually expensive, but these days you can find inexpensive microphones that have an excellent performance. The frequency response of such microphones might not be perfectly flat, but you can compensate its response if you have a frequency response data of that microphone.

For measuring a sound pressure level (SPL), you need a sound level meter or an acoustic calibrator for calibrating the input signal level to the computer. If you don't calibrate your system, you can measure only the relative sound levels. 

You can find more information about microphones and other equipments in this page. Additional devices for sound measurement 

  [Back] [Up]

The difference of the version of your software (RAL, RAD, RAE, DSSF3, etc.) is unclear.
Our software is mainly divided into two series, RA series (RAL, RAD, RAE) and DSSF3 (Light, Realtime Anallyzer, Full-system version, Environmental Noise). 

Functions in the previous version of DSSF3 has been packed into the lower price of software and is released as RA series. For example, RAL consists of the most basic measurement capabilities including:

  • signal generator
  • peak level monitor
  • power spectrum
  • 1/3 octave analysis
  • TEF (time-energy-frequency) display
  • oscilloscope

Other advanced functions, such as the impulse response, ACF/CCF measurement, and environmental noise measurement are available in higher version of the program (RAD and RAE). 

New version of DSSF3 (version 5) has been released on February 2003 and almost all functions have been continuously upgraded to reflect users' request and to incorporate advanced measurement capabilities. Update history can be seen in DSSF3 News.

See the function list for comparing the available functions in each version.

  [Back] [Up]

Give me advice how to use this software.
You can find various application notes of these measurement functions in Introduction to Sound Measurement. Some of the examples are briefly described below. You can see other information in this Q&A. Go to Application in specific fields and Measurement tips sections. 

Program manuals and user support documents can be found at http://www.ymec.com/store/en/manuals.htm

Even if you have few knowledge and experience of sound measurement, you can start the measurement by just clicking the "Start" button on the measurement windows. Complex settings can be ignored at first, because these are automatically set by the program. Signal generator, oscilloscope, FFT analyzer would tell you many things about sound. As a next step, follow the instructions in the operation guides and the measurement reports. You can learn how to use RA step by step.

  [Back] [Up]

What kind of measurements are possible in RAL? 
RAL consists of the most basic measurement capabilities, such as the spectrum analyzer (power spectrum, 1/3 octave band analysis, correlation meter), signal generator, and oscilloscope. You can find various application notes of these measurement functions in Introduction to Sound Measurement. You can see other information in this Q&A. Go to Application in specific fields and Measurement tips sections. 

Some of the application examples are briefly described below. 

1) measurement and diagnosis of motor and engine performance
It is said that some people can diagnose the performance of a motor only by hearing its operation sound. In our experiment, we tried to measure the motor performance using the power spectrum and the autocorrelation function, that represent the rotation speed (rpm) or the rotation stability. The motor sound actually changes by changing the power supply or by cleaning up fans. Read more...

The same measurement might be applied to the car and motorcycle engines. The exhaust note is very important for maintenance and tuning of the race car, because the sound directly reflects the condition and the performance of engines. Rotation speed and vibration frequency can be measured from the engine sound. Read more...

2) measurement and diagnosis of PC's soundcard
In any kind of measurement, it is very important to know the quality of the measurement system itself. When using the PC based measurement system, the most critical part is the sound card. Important things are: measurable frequency range, wide dynamic range, low internal noise, distortion, and other artifacts. It is important to know these performance before the measurement. It can be tested using the sweep tone and the spectrum analyzer. Any problem of the device, such as the distortion and the oscillation can also be revealed by the oscilloscope and THD analyzer. Read more...

3) noise measurement in a living room and a bed room
We are surrounded by many noises in our home. Almost all of the electrical appliances, for example, air conditioner, refrigerator, cleaner, emit noise. These sounds are not so loud, but are sometimes very annoying because the specific frequency component always exist. It might be caused by a mechanical breakdown or some accidents of the appliances. It can be checked using the 1/3 octave analyzer. Of course, the sound from outside, such as a traffic noise or a construction noise, can be investigated. Read more...

4) test and adjustment of home audio and car audio
Real-time analyzer (RTA) is originally used for the audio measurement. Basic measurement is the 1/3 octave band analysis of the pink noise response of the loudspeaker output. Combination of the sweep signal and the power spectrum is also a powerful measurement tool. It can reveal the distortion and noise very clearly. Read more... 

5) analysis of speech and singing voice, musical instruments
RAL can be used for tuning instruments, measuring frequency components of speech, or analyzing voice quality. Realtime spectrogram (note that this is a new function of DSSF3) is a valuable tool for a voice training and a speech therapy. 

6) Sound measurement for medical diagnosis
It is widely recognized that auscultation is a very effective method in detecting heart diseases and lung diseases in clinical diagnosis, because the auscultation sound contains much useful information about the activity of inner organs such as heartbeat, blood flow, breathing. We are trying to record the medical sounds using a stethoscope microphone and analyze its characteristics. Read more...

You can try measurement by yourself. Note that almost all functions of RAL have been upgraded and many advanced features have been newly added in DSSF3. For example, THD analyzer, Spectrogram, Phase meter, and Sound recorder are very useful in the audio measurement and analysis. Update history can be seen in DSSF3 News. For comparing the available functions in each version,  function list is available.

  [Back] [Up]

I want to buy the sound measurement software for using it for the adjustment of my audio room. I have some questions about it.

Q1. Which software should be purchased for the purpose of the following measurement?

  1. The frequency characteristic both at 1m from a speaker and a listening point.
  2. Reverberation time of a listening room for each frequency range. Time until sound pressure is halved in an impulse response
  3. Time alignment of each speaker unit in the crossover frequency of a multi-way speaker. The purpose is to make a phase gap minimum. I plan to adjust a unit position to time alignment by the following method. 1) Impulse responses are measured on the crossover frequency of each unit at the listening position. 2) The distance between units is calculated from the time lag of the onsets of each unit response. 3) To compensate time lag, a unit position is adjusted. Is this method right? Or are there other methods?


Q2. The personal computer to be used is IBM ThinkPad X20, which has a stereo microphone input, a stereo line input (input sensitivity is adjustable), a stereo headphones output, and a stereo line output. Also, the comparatively high quality microphone amplifier and mixer are available.

In your Q&A site, it is said, "Simultaneous output and input is possible if the Sound Blaster compatible A/D and D/A can be used simultaneously. A PCMCIA correspondence sound card can also be used." Is a duplex type sound card required for measurement of the impulse response time as in questions 2 or 3 above?

A1. RAD and DSSF3 Full-system (or higher versions) are capable of analyzing the impulse response. Our recommendation is DSSF3 Full-system, because the Realtime Analyzer is much improved in comparison with RAD. For example, phase meter and distortion analyzer have been newly added, and it is compatible with the latest OS and USB audio interface. 

1. The frequency characteristic both at 1m from a speaker and a listening point ... Measurement of the frequency response can be performed easily by using the pink noise and the octave band analyzer. The test signal can be generated by the signal generator of the Realtime Analyzer. 

2. Reverberation time of a listening room for each frequency range...  Impulse response measurement is performed by the Realtime Analyzer using MLS (maximum length sequence) or TSP (time stretched pulse) signal. Measured impulse response is then analyzed by the Sound Analyzer. For example, the arrival time of the direct sound from a speaker unit and the delay time of the reflective sound is obtained. The reverberation time and the inter-aural cross-correlation can be measured for 1/1 or 1/3 octave frequency band.

3. Time alignment of each speaker unit in the crossover frequency of a multi-way speaker... The method you mentioned seems right. Another possible way is to use a phase meter. 

A2. Full duplex type soundcard is necessary to perform the impulse response measurement for simultaneous output and input. 

  [Back] [Up]

Which software is suitable for a design of speaker crossover network? I want to measure the performance of my design and adjust it by using the spectrum analyzer.  
We recommend DSSF3 Realtime Analyzer for this purpose. Real time measurement by the octave band analyzer, power spectrum, and phase meter, or the distortion measurement by the THD analyzer will help adjustment of speaker. 

The problems in designing the crossover network are described in Don Davis, "Sound system engineering". Some important points are quoted below.

1. Choosing the crossover frequency that match the directivity of driver units.

2. Choosing the proper filter slope that
  a) keeps high frequency transient distortion at a low level, and
  b) reduces the low frequency distortions.

3. Matching the phase characteristics of the crossover network and the driver. 

4. Matching the impedance of the crossover network and the driver.

  [Back] [Up]

Is it possible in RAL to observe the waveform of the amplifier output?
It is possible to measure all the signal that can be fed to the soundcard, such as the amplifier, digital tape recorder, microphone, or electronic probe. Measurement setup can be found in this application note: Setup for using 2ch oscilloscope
  [Back] [Up]

I want to measure the sensitivity and the frequency response of my old microphones (BK-5B and TCA-77D). How can I measure them using your software? 
To measure microphones precisely we need equipments such as anechoic room and high quality monitor speaker. But it is difficult for many people. As a simpler and more convenient measurement, you can compare your microphone with a high quality microphone of which characteristic is well known. Output a pink noise or sine sweep from a loudspeaker, and measure it by two microphones. Comparing of their spectra tells you differences of them. 
  [Back] [Up]

Can I output a measurement data of RAL to a video deck as a movie in real time? 
It is possible if your PC has a video output. In this case, a full display of your PC is recorded. 
  [Back] [Up]

I want to measure the frequency response of my car audio system at the driver's position. Which software is suitable for this kind of measurement? Also, do I need any other device, such as a microphone, soundcard, pink noise source, etc?
For equalizing the frequency response of an audio system, a basic measurement is to feed a pink noise to the system, pick up its output sound by a microphone, and measure it by the 1/3 octave analyzer. See the following application notes to know about the measurement procedure. Audio measurement report

We recommend DSSF3 Light for this kind of measurement. Internal signal generator and the spectrum analyzer might be enough. For a more advanced measurement and adjustment, DSSF3 Realtime Analyzer is recommended. This version includes the distortion analyzer and the impulse response measurement function.

In the measurement, you need to output test signals such as pink noise, 1 kHz tone, and sine sweep from your audio system. It is convenient to record these signals on a CDR. Set the microphone at the listening position, replay the CD, and measure sound. Adjustment of the equalizer, amplifier's volume and valance, positioning of the loudspeakers can be performed in real time. 

Before the actual measurement, check and adjustment of the measurement equipments (PC and microphone) is necessary. See the RA's program manual for detailed instruction. If the performance is not good and if you prefer better one, you can replace the soundcard and microphone. See the following page to know about the additional equipments. Additional devices for sound measurement

  [Back] [Up]

I want to analyze a sound from a wristwatch. What kind of microphone should be used?
For this kind of measurement, microphone should have high sensitivity and good frequency response. As examples we recommend Audio-Technica AT9470 and SONY ECM-MS907. These microphones can be used for general purpose. 

It is good to measure in a quiet room. Set the microphone close to the watch and increase the input level. If these microphone don't work well, another choice is to use a contact microphone. For example, we have made a stethoscope microphone to record a heart sound. 

  [Back] [Up]

I want to use RAL for equalizing my car audio system. How can I compensate the microphone's frequency response for this measurement? 
Microphone's frequency response can be compensated on the calibration window of the FFT analyzer. But for this calibration, microphones frequency response has to be known. If your microphone's spec sheet doesn't show this information, it is difficult to compensate its response. We recommend to purchase a microphone that is sold as "measurement microphone" or "calibrated microphone". You can find some of our recommendation in this page. Additional devices for sound measurement

However, we think you don't need to be too sensitive about the flat frequency response of the microphone. Usually, microphone's response is attenuated in low and high frequency ranges. It is no problem in measuring the mid frequency range, that is important for adjusting the channel divider's crossover frequency and equalizer gains. If you are using such an uncalibrated microphone for equalizing audio systems, replay pink noise and measure 1/3 octave response without compensation. Then, adjust your system until the 1/3 octave response becomes a smooth curve without sharp peaks. 

  [Back] [Up]

I am considering to use DSSF3 for noise measurement. But I cannot use PC at the measurement site. So I want to first record noise by DAT and then analyze it later. Is it possible? 
Yes, you can measure the recorded sound. But note that the recording level has to be calibrated to measure the absolute noise level (sound pressure level: SPL). Without calibration, you can measure only the relative sound level. What is important is to know the actual SPL of the sound recorded on the tape. See the following application note for how to measure SPL from the recorded sound. DAT and DV recording for outdoor sound measurement (Instruction for advanced use 3) 
  [Back] [Up]

In RAE, is it possible to calculate the noise level of complex noise? I want to know the total noise level of several sources measured separately. 
If each sound source was recorded, they can be synthesized in the sound editing software (for example, Adobe Audition) and then measured in RAE. Or, the total noise level can be calculated from the noise level of each source by using the following equation:

 L_total=10*log10(10^(L1/10)+10^(L2/10)+10^(L3/10)+...10^(Ln/10)).

For example, total noise level of two sounds with levels of 90 dB becomes 10*log10(10^(90/10)+10^(90/10) = 10*log10(2*10^9) = 93 dB. 

SPL of the wav files can be more easily measured using DSSF3 Light. See the following application notes. 

Measurement data management in Realtime Analyzer

Operation of a Sound-level Meter 2

  [Back] [Up]

Can RAE be used for evaluating the footstep noise or impact noise in the apartment? 
Yes, RAE is recommended for your purpose. 

Because the duration of the footstep noise is very short, it is difficult to measure it by the sound level meter with a usual setting. To measure such a sound, very short integration time of sound signal is needed. EA (Environmental noise Analyzer) of RAE and DSSF3 can measure it, by setting the integration time short, e.g. 10 ms. 

EA is also equipped with the automatic measurement function, that start the measurement automatically when the sound level exceeds the specified trigger level. This function can be used if the level of the background noise and the footstep noise are well separated. Some of our users are monitoring noise while sleeping. Even the averaged SPL of such an impact noise is low (e.g. 40-50 dB), its instantaneous level is sometimes very high (e.g. 70-80 dB). This corresponds to the car noise. Also, its relative level becomes high, because the background noise is generally low at night. So, it is very annoying and sometimes very dangerous for human health. 

For how to use EA, see the EA's operation manual. Step by step instruction is available.

  [Back] [Up]

Can I measure noise by RAL? Do I need other equipments than PC and software?
Yes, RAL can be used in the noise measurement. But note that RAL is a functionally limited. We recommend DSSF3 for noise measurement. Necessary equipments are: microphone + acoustic calibrator, or sound level meter, and soundcard. 

Basically, noise measurement is performed by connecting the AC output of the sound level meter to the soundcard's input. Other microphones than the sound level meter can also be used as input. But in this case, the input level has to be calibrated using the acoustic calibrator. In any cases, calibration is necessary to measure the absolute sound pressure level. If the calibration is not done, you can measure only the relative sound level. 

See the operation guide in the RA's program manual for microphone calibration and how to use the sound level meter. See Additional devices for sound measurement for more information about the equipments.

Measurement software significantly extend the function of the standard sound level meter. For example, we can save the measurement results, perform the frequency analysis (octave band analysis), and so. Even the lowest version of DSSF3 (DSSF3 Light) is equipped with the data record function that can save the octave band analysis data as a csv file. DSSF3 is also equipped with the standard time constant setting (FAST/SLOW) and the 1/1 octave band analyzer. From the measured data, averaged noise level, min, max, or equivalent noise level (Leq) can be calculated easily.

To perform a long time measurement, EA (Environmental noise Analyzer) is recommended. For example, EA can perform the automatic measurement when the sound level exceeds the specified trigger level. The noise is saved as a sound file with the calculated acoustic parameters. The data can be further analyzed in SA (Sound Analyzer). EA is available in RAE and DSSF3 Environmental Noise.

EA can also measure impulsive noise, which is difficult to measure using a standard sound level meter because its duration is very short. To measure such a sound, very short integration time of sound signal is needed. EA can measure it very accurately, by setting the integration time short, e.g. 10 ms. 

  [Back] [Up]

Can I use the oscilloscope to test currents on small electronic systems?
Realtime Analyzer's oscilloscope is usually used to measure sound signal. But the electronic circuit can also be measured by using the electronic probe as an input device. Here is a report for measuring a small electronic systems. Connection of probes for oscilloscopes
  [Back] [Up]

Is it possible to input the external electronic signal?
Yes. You can use the electronic probe as an input device. See the following application note:
Connection of probes for oscilloscopes, in Introduction to Sound Measurement.
  [Back] [Up]

I tried to analyze a low frequency noise by the 1/3 octave analyzer. But the level (dB) is displayed as a minus value. How does it display the absolute sound level?
As a default, the FFT analyzer displays the "relative" level using a reference of full-scale sine wave as 0dB. To display the absolute sound pressure level, microphone's input level has to be calibrated by using a sound level meter or an acoustic calibrator. For how to do this, see the RA's operation guide and how to use the sound level meter
  [Back] [Up]

How can I analyze an existing wav file by RAL?
In RAL, wav files can not be loaded directly. You have to use a sound player (e.g. Windows Media Player) as an auxiliary tool. Set the input device of RAL to "WAVE" or "Mixer", start the FFT analyzer, and play the wav file. In this configuration, a wave signal is D/A-A/D converted before measured by RAL. It is important to adjust the input/output volume to prevent distortion. 

RAD or RAE can load a wave file directly from the running ACF window. In this case, you don't need to worry about distortion. A wav file itself can be measured. Also, it is easy to play the loaded file and analyze it by the FFT analyzer simultaneously. DSSF3 is equipped with the sound recorder. It is much easier to analyze wav files than the previous version. We recommend DSSF3 Light for analyzing wav files. 

  [Back] [Up]

In RAL, is it possible to measure the line-input and the microphone input simultaneously?
It is impossible to select two input devices (this case, line-in and mic) at the same time. It is a limitation of Windows' sound control. 

To measure two signals from different input terminal at the same time, you should connect one input to the Left channel, and another input to the Right channel of the same input terminal (e.g. Line-in). See the application note of the oscilloscope for the measurement setup. 

If you have an external mixer device, input signals can be switched easily. 

  [Back] [Up]

How can I measure sound by the octave band analysis and save the data?
This is a most basic procedure in audio measurement. You can see this application note Measurement data management in Realtime Analyzer. Measurement procedure is briefly described below.

1) Open the FFT analyzer in RA (Realtime Analyzer), select the "microphone" as the input device, and click the start button. Sound is captured from the PC's built-in microphone, and the measurement starts immediately. Detailed settings can be ignored at the beginning. 

2) The measurement window can be captured by clicking the "Screen Copy" button. Image database MMLIB can also be used to manage the measurement data. 

3) Numerical data can be saved on the octave band analyzer. Click the "Data Record" button to open the data record dialog. 

As for the additional equipments such as the external microphone and the soundcard, see Additional devices for sound measurement

  [Back] [Up]

How can I use RA for the adjustment of audio system? I am interested in adjusting the crossover network, positioning the loudspeakers, and testing the amplifier.
For those purposes, a basic measurement procedure is to output the test signal from the loudspeaker and measure its output by the octave band analyzer and the spectrum analyzer. As a test signal, pink noise, white noise, single sine tone, and sine sweep are commonly used. 

For example, balance of high and low frequencies can be easily checked by the octave band analysis using pink noise. Crossover point of the network can be checked more in detail by the power spectrum of the white noise or sine sweep. If you change some settings, it will be immediately reflected in the measurement results. You can adjust your system by seeing the results in real-time. 

Note that the output signal from the speaker is greatly influenced by the placement and positioning of the speaker. Perhaps you can find best positions by seeing the measurement data and listening to the sound. 

Single sine tone can be used to test the distortion or signal leak of the amplifier by observing the output signal on the oscilloscope or the spectrum analyzer. 

  [Back] [Up]

Can I measure the performance of speaker network itself?
Yes, it is possible to measure the performance of speaker network by inserting a resistance instead of a speaker. Feed a test signal to the circuit, and measure the output voltage. 

Basically, speaker's output sound is measured by the FFT analyzer for checking the performance of speaker network. But in this case the results are affected by the characteristics of the speaker unit. So, we need a high quality monitor speaker unit. As an alternative way, the electronic measurement stated above might be available.

  [Back] [Up]

Is it possible to estimate the location of the sound source, like a tool for finding the epicenter of the earthquake?
If you use two microphones, the angle of incident of sound can be estimated using the cross-correlation function. See this application note: Analysis of sound direction from the cross-correlation. It may be possible to estimate the location of sound source by placing three sets of microphones orthogonally in x, y, and z axes, though we have not confirmed it yet.
  [Back] [Up]

I'm a dentist. I want to measure change in voice quality of patients before and after the treatment. What criteria of sound should I measure? For example, frequency, peak, and dB values. Also, which software version is suitable for my purpose?
It is recommended to record sound to a computer and save it in a wav file using the sound recorder, and measure it using the FFT analyzer. For measuring voice quality, power spectrum, octave band analyzer, and spectrogram are useful. These functions are available in DSSF3 Light. Measurement data can be saved as a screen copy of the measurement window or the numerical data of the octave analysis (frequency [Hz] and amplitude [dB]). 

See the following application note. Singing voice analysis by the spectrogram, Analysis of Japanese voice, Measurement data management in Realtime Analyzer

 

Basically, human voice consists of several harmonic frequencies. If the voice changes, it will appear as the change in the spectrum. We think that if you store results for each patient continuously, you can compare their spectra and find changes. 

If you need more precise measurement, you can use the Sound Analyzer. This module is available in DSSF3 Full-system. Some important acoustic parameters can be analyzed with a high temporal resolution. For example, time history of the sound levels, pitch, and pitch strength are important factors in determining the perceived voice quality. See Introduction to the autocorrelation function for more information.

  [Back] [Up]

I want to use the sound measurement software for my child's homework. I want to measure tone height or wavelength of voice of several birds and insects. I think the oscilloscope is suitable for this purpose. What do you think? I just tried the software but I don't understand technical terms such as level, sweep time, delay time, and trigger. I would be appreciated if you could teach me these terms and how to use the software.
It sounds interesting to measure voice of birds and insects. Oscilloscope can be used for this purpose. Spectrum analyzer can also be used to measure the voice wavelength (frequency).

Our software is designed to work automatically. Even if you have few knowledge and experience of sound measurement, you can start the measurement by just clicking the "Start" button on the measurement windows. Complex settings can be ignored at first, because these are automatically set by the program. Signal generator, oscilloscope, FFT analyzer would tell you many things about sound. As a next step, follow the instructions in the program manual and the application notes. You can learn how to use the Realtime Analyzer step by step.

As for the technical terms of the oscilloscope, you can find many useful information on the web. Because the user interface of our software resembles actual instruments, it is easy to understand the meaning of items on the measurement screen. 
  [Back] [Up]

When generating the sweep signal and measuring the loudspeaker output in the spectrum, the difference between low and high frequencies becomes large (above 15 dB). What is the reason of this difference?
Generated signal is the logarithmic sweep, in which the frequency increases with a fixed rate of octave change per time (Octave/sec). This means that every octave contains the same energy. Its frequency characteristic is same as the pink noise, so it will become a flat response when it is measured by the octave band analyzer. See this application note for more information about the sweep generator and the frequency response measurement.
  [Back] [Up]

What should I do if the program is hung (and/or stops responding) by the problem of the OS or the driver?
If you use WindowsXP, try a command "taskkill".

C:\>taskkill /F /IM pcaudio.exe"

  [Back] [Up]

All of a sudden, the font type and size was changed and also the window size was changed.
When other software is uninstalled, the font type (MS Sans Serif2) currently used by the "DSSF3" may be removed from your computer. Consequently the window size changes. If you add the font to your computer again, probably it will be restored. However the best way to restore is that you reinstall the program and then execute the program updates through the internet. (Both your license and data are left as it were.)
  [Back] [Up]

When the program (RAL) is started, a dialog "Can't use mixer." is displayed and the program does not start. Can I ask your advice about this?
This error occurs if the audio device is unavailable on your computer. Check your audio properties in Windows control panel. If the audio device is not working normally, try reinstalling the soundcard driver. Another possible reason is that RAL has not been installed properly, because your Windows installer program is old. In this case, apply the Windows update and install RAL again. 

We have been reported some USB audio devices didn't work with RAL/RAD/RAE, but worked with DSSF3. So, we recommend you to try DSSF3.

  [Back] [Up]

When I clicked on the shortcut icon to start the program, the following message was displayed and the program was not able to start.
Cabinet file 'Data Cab' is not found. PcAudioLTE.exe can not be installed. Please advise me.
First, uninstall the program and then install again. This operation may fix the problem. If this does not solve the problem, apply the Windows update to refresh the Windows' installer program. Then, install RAL again. 

Please remember to backup the DATA folder, in which the measurement data is stored, before the installation. Otherwise, your previous data will be deleted because the installer program overwrite the DATA folder.

After reinstallation, your registration information is left as it was. When the program requires a Registration Number after reinstallation, input the registration number we sent to you before. If this number is refused, please contact us by email.

  [Back] [Up]

I updated my program through internet. After this, a message that "licence.dll is not found" always appears when the program starts.
The module is old. Please download and install the program again. If it happens again, the software might have been installed improperly. Apply the Windows update to refresh the Windows' installer program. Then, install the software again.

Please remember to backup the DATA folder, in which the measurement data is stored, before the installation. Otherwise, your previous data will be deleted because the installer program overwrite the DATA folder.

After reinstallation, your registration information is left as it was. When the program requires a Registration Number after reinstallation, input the registration number we sent to you before. If this number is refused, please contact us by email.

  [Back] [Up]

Do you have literature concerning this software?
Please refer to the following URL.

Cooperator in development: Professor Yoichi Ando, Graduate School of Science and Technology & Faculty of Engineering, Kobe University
http://www.andolab.org/index_e.html

Research Papers related to Diagnostic System for Sound Fields
http://www.ymec.com/doc/study2/
  [Back] [Up]

What is the online update?
Online update will keep your software up to date. Connect to the Internet, start RA, SA, or EA, and select the "Online update" from the Help menu. The program searches the latest updates and install them automatically.  

The update information of the DSSF3 can be found at the DSSF3 news

  [Back] [Up]

My question is about the parameters that SA 5,0,5,6 use to count frequency spectrum in a spectrum sub menu. I mean what kind of 'window', FFT size and percentage of overlap it uses for calculation. Unfortunately, I could not find it in on-line guide you have.
Parameters in the calculation of the spectrum in SA is set as follows.

FFT size: Integration time (decided in the calculation condition window)

percentage of overlap: Running step (decided in the calculation condition window too)

window function: rectangular

The FFT size and the overlap size is set as time (in second), so the actual FFT size in sample is Integration time * sampling rate. The overlap size in percent is (Integration time - Running step) / Integration time. The data portion that is used for the calculation is indicated by the blue area in the waveform display. The figure below shows the example, in which data was calculated with the integration time of 0.5 s and the running step of 0.1 s. The waveforms at 0.1 s and 0.2 s are shown here for illustration.

  [Back] [Up]

Please tell me how to buy the software and how to make a registration.
At first, download the installer program from the products web site and install the software. The software can be used without any limitation during a trial period. After checking the operation on your computer, please make a payment. We accept credit card and bank transfer. After the payment, we will provide a registration number (password). 

The procedure is summarized in How to purchase the license

  [Back] [Up]

I sent you my hard key, but I have not received my registration number from you yet. What is the problem?
Please check if you use spam filters. We heard from one of our user that he found the message from us in his trash box. His spam filters did not accept our message as it did not originate at ymec.com, the approved domain name he was expecting.

We are trying to send registration numbers from ymec.com to avoid such problems.

  [Back] [Up]

I am using RAE (ver.2.0.0.1) for adjusting the car audio system. Before, I was using the microphone input of PC to record sound, but recently I bought a USB sound device, Edirol UA-1X. However, after connecting this device to PC, I can't measure sound. Mic or line-in does not appear in the input device selection in RAE. How can I do it? I am now thinking of purchasing another device, e.g. UA-25. Does it work with RAE?

Check the Windows' volume control panel. If the recording device such as mic or line-in does not appear on the panel, the device does not work with RAE (also RAD and RAL). The reason is that the sound device does not use Windows' sound mixer but use its own sound mixer.

In the case of UA-3, we have been reported that Windows volume control is not necessary, because the input volume is controlled by the hardware volume of UA-3. In that case, the measurement has become available after selecting the "USB audio device" as the Preferred device on the Sound and Multimedia control panel. The signal come from UA-3, although the "Input Device" column was blank and the Input Volume could not be controlled from the program.

However, we have been reported from many users as for the problem of Edirol products. It seems UA-1X can't be used for sound input. UA-3 is also problematic in many cases. UA-5 works fine. We can't say about other products. 

We recommend you to try DSSF3, because we have been also reported that some USB device did not work with RAE, RAD, and RAL, but worked well with DSSF3. 

  [Back] [Up]

I am considering to purchase software and equipments for measuring noise inside the car. I found at your website that I can measure noise using a video camera and an external microphone. Do I need other equipments?
We use a video camera in our measurement report (e.g. automobile noise analysis) for recording sound and movie at the same time. You can measure sound without a video camera, but it is convenient to use it, because you can remember the situation of the measurement. 

If you use a digital video camera or a DAT recorder, it is important that the recorder has a manual recording level control. In addition, you need a sound level meter or an acoustic calibrator for measuring the sound pressure level (SPL). Without calibration, you can measure only the relative sound intensity. For how to perform a measurement, see the following application notes.

DAT and digital video recording for outdoor measurement

Operation of a Sound-level Meter 2

Additional devices for sound measurement

Measurement equipment example

  [Back] [Up]

I am considering to purchase software and equipments for measuring noise inside the car. I plan to measure the characteristics of noise sources (e.g. engine, exhaust, gear, and road noise), difference between cars, effect of absorbers. Which version of your software is suitable?
We recommend DSSF3 Full-system or Environmental noise.

Even DSSF3 Light can perform the spectrum and the octave band analysis. But we think you need Sound Analyzer for your measurement, because you measure a lot of items. It is more important to construct a measurement database than the measurement itself. It may be difficult to manage the measurement data by DSSF3 Light. 

Cooperation of Realtime Analyzer and Sound Analyzer helps multidimensional sound analysis by use of various acoustic parameters. In addition to the conventional FFT analysis, a newly developed ACF / CCF is used for analyzing several acoustic qualities and spatial qualities of sound. Analyzed information is stored in the huge database, and is smoothly displayed in an intelligible set of graphs. This is the original and the advanced functions of DSSF3.

For saving and printing the measurement screen as picture files, an image database software, MMLIB is also recommended. Measurement window and graph images can be easily stored to construct a measurement database.

  [Back] [Up]

I found some articles about Realtime Analyzer in your website. I want to know more about the software. Do you have a brochure or a manual of the software?
We are publishing documents about the software in our website. Online program manual can be reached from the following pages. Online manual can also be seem from the Help menu of the software.

Realtime Analyzer http://www.ymec.com/manual/era/index.htm

Sound Analyzer http://www.ymec.com/manual/esa/index.html

Environmental noise Analyzer http://www.ymec.com/manual/esa/index.html

We are receiving a lot of request for pdf manuals, but at the moment only the online manual (html version) is available. 

  [Back] [Up]

I have text files and .dat files (raw data in the time domain). I cannot find a way to load them into DSSF3 (Realtime Analyzer) and analyze them using 1/3 octave features. Is it possible to use DSSF3 in this manner?
You need to convert dat files into wav files, or other standard audio formats (e.g. mp3, aiff, au) that are supported by most audio players. Wav files can be loaded by DSSF3 directly using the sound recorder. Other audio format can be played by the audio player and then analyzed by DSSF3.

We found that GoldWave Digital Audio Editor http://www.goldwave.com/ can do what you want. You can open a raw data and then save it as a wav format.

  [Back] [Up]

I just downloaded a trial copy of DSSF3 Ver.5 but am unable to test or perform any analysis on my impulse response wave file, attached. I would like to be able to run analyses on similar files. Your downloaded trial software tells me that it is the latest, updated version and your website tells me that it should be able to read my *.wav file. Please check on this and tell me what is my error.
We found that your wav file is saved as Microsoft ADPCM format, slightly different from the standard Microsoft PCM format, though both are ".wav". See for more information in Microsoft web site http://support.microsoft.com/support/kb/articles/Q89/8/79.asp.

At present, DSSF3 enables to read only PCM format, so your file could not be read. To solve the problem, you need to convert your files to PCM format. Several converter programs are available on the internet.

GoldWave http://www.goldwave.com/
AudioAlchemy WAV Edition http://www.convertmusic.com/wav.asp
Visual MP3 To Wav Converter http://www.visual-mp3.com/mp3-to-wav/
  [Back] [Up]

I can't install the program. When I run the installer, I get a message INST MSIA.EXE NOT FOUND. What should I do?
This is a problem of Windows' installer agent. Before running the installer of our program, you should install one of following programs, depending on the version of Windows OS. 

Instmsia.exe for Windows 98 or ME:

Instmsiw.exe for Windows NT, Windows 2000 or Windows XP:

 

[Back] [Up]


We are using your RAE program, and we now find that we have an excessive amount of data files we are no longer interested in, stored on our hard drive. Over three gigabytes to be exact. How can we delete specific data files, without losing files we still want, or without endangering the programs ability to store fresh data? The "delete" function only seems to be applicable to the entire "stored files" folder, and we're a little afraid of deleting our ability to store future files using it.
How to delete stored data is different for the type of data. Data type is shown in the left column of the main window of Sound Analyzer. Following procedures are same for RAE and DSSF3.

1) Impulse Response
Open the Impulse Response window from the Realtime Analyzer. Click "Load" button. Folder and Measurement data are displayed. To delete a specific data in a specific folder, select the folder and then select the data, and click the "Delete" button. To delete a whole folder, select the folder and click the "Delete" button. 

2) Running ACF
Open the Running ACF window from the Realtime Analyzer. The following procedure is same as above.

3) Noise Measurement
There is no way to delete the specific data of this type. Data is stored in the files "NMS.BIN" and "NMS.DBF" in the DATA folder in the program folder. If you don't need whole data, you can delete these two files. But if you need some of data, you have to backup these files to the another hard disk.

Finally, when you want to clear all the data, delete the DATA folder. After this operation, the new DATA folder is created so that you can start the measurement again. If you are using DSSF3, setting utility (DSS.exe) is available for the management of the measurement data. See the following page for more information. Measurement data management in Realtime Analyzer (Introduction to Sound Measurement)

 

[Back] [Up]


Can the FFT Analyzer use text based microphone calibration files?
No. Unfortunately, the calibration data can't be loaded from a text file. Data has to be entered by hand on the calibration window. Please see the program manual for how to do it.
 

[Back] [Up]


I plan to use the system for movie theater sound alignment. Each channel of the digital sound processor is equalized using an "X-Curve" weighting. In RA, is there a way to use different weighting types (X, Inverse X, or a custom weighting)?
RA only has A-, B-, C-weighting. Other weighting curves are not equipped. But you can create your own weighting curve by entering "Frequency" and "Level" values on the calibration window.
 

[Back] [Up]


Can the FFT Analyzer use a calibration file for the sound card to calibrate out the response of the sound card?
There is no way to calibrate the soundcard automatically. But you can do it manually. Once you measure the frequency response of the soundcard using pink noise and 1/3 octave analysis, you can make a calibration file of the soundcard on the calibration window. When you want to calibrate both the soundcard and the microphone, however, you have to add the Level values at each frequency before making the file on the calibration window. The software does not have a way to sum up two calibration files.
 

[Back] [Up]


Could You explain what does Frequency Weighting mean?
Frequency weighting curve is used to mimic the sensitivity of our hearing. Especially A-weighting is commonly used in the noise measurement. Low and high frequency components will be reduced, because our sensitivity to these sound is very low. Please see the following webpage for more information.
http://hyperphysics.phy-astr.gsu.edu/hbase/sound/acont.html
 

[Back] [Up]


I want to make a Waterfall analysis of a wave file. I can load the sound file on the recorder and make an analysis by the FFT analyzer. However, the problem is that I see the plot just in a moment of time. I mean, the graph disappears at once. I think there is some option to make the Waterfall plot of entire signal. If You know how to do it, please explain me.
For this purpose, you should adjust the time range of the waterfall display to the length of the sound file. The display time range is shown in the left bottom of the graph, like t=928.8ms. This time range is decided by multiplying the two parameters: Resolution T:ms and Number of Data. For example, 46.4 * 20 = 928. Resolution T is an interval of the FFT operation, that is decided by FFT size / Sample Rate / Time Resolution *1000. It is 4096 / 44100 / 2 * 1000 = 46.4 ms. It is somewhat complicated, but you can adjust these parameters to get an appropriate setting. 
 

[Back] [Up]


Could it be possible to measure the reverberation time from a recorded impulse signal of a room exited with, for example, a pistol shot? 
Realtime Analyzer doesn't use a pistol shot as an excitation signal. Rather, MLS (Maximum Length Sequence) or TSP (Time Stretched Pulse) signals are used for the measurement, because those signals allow much more precise and stable measurement than other signals such as a pistol shot, balloon explosion, and clapping hands. The program generates the excitation signal, records it, and processes it automatically. This is the standard measurement procedure of our software. It is very easy and takes less time and effort.

However, you can record the response of the pistol shot and measure the reverberation time from that response. It may take more time than the standard measurement, but is not practically difficult. The procedure is as follows.

1) Record the signal on the Recorder window.
2) Save the signal as a .wav file.
3) Load the wav file on the Impulse Response window.
4) Save data into the database.
5) Analyze data in the Sound Analyzer.
 

[Back] [Up]


I want to know the Effective Value of the sound signal (RMS value). But in FFT Analyzer, it seems that I can only get the instant point value during record process. How can I obtain the RMS value of the recorded waveform? 
RMS values of sounds can be measured using the smoothing or the moving average. Moving average is a simpler process, that calculates the average for a specified period. Smoothing is a process of the exponential averaging. Practically, smoothing is recommended because it is same as the operation of the sound level meter. Select the time constant of fast (125 ms) or slow (1 second) to record the RMS levels.
 

[Back] [Up]


In the Octave band analysis, I select smoothing of 1s(slow) mode. And in the date recording dialog, I select automatic, 1s interval mode. But I found the recoded data in data recording list is different from the "Level [dB]" value in the Octave band display. Why?
In the Data Recording window, an instantaneous data displayed in the octave band graph (and "Level" display) is captured at a given interval (this time, 1s). This data is not always same as the "Level" display at a moment because the sampling timing is different. You can see the sampling timing of the octave band graph in "Resolution [F:Hz, T:ms]" area. Perhaps the time resolution is much faster than 1s. So, you can't follow the Level display during a measurement. 
 

[Back] [Up]


I downloaded and installed DSSF3 but didn't use it in the time allowed for demo. Is there a way to extend the trial period?
Unfortunately there is no way to extend the trial period. If possible, please try it on another computer. You can have 30 days trial on each computer.
 

[Back] [Up]


Your SA Program Manual describes how to calculate Speech Transmission Index (STI). Does the DSSF3 perform these STI calculations automatically?

In order to perform STI measurements we need to apply a signal that is modulated band-pass noise (MTF = modulation transfer function)). Is the DSSF3 capable of generating the MTF signals for making STI measurements? Do you sell a CD that has these MTF signals?
Yes, DSSF3 can perform the STI calculation. However, it does not use modulated band pass noise in the measurement. MTFs in each octave band are calculated from the "impulse response" measured by the Realtime Analyzer using MLS (maximum length sequence) or TSP (time stretched pulse: like a sine sweep) signal. Then, the impulse response is analyzed by the Sound Analyzer to obtain the STI and other acoustic parameters.
 

[Back] [Up]


What is the minimum package (software + hardware) for measuring noise 
level? I am a home user and I want to measure the noise of airplanes passing over my house. What is the minimum package I need to cover this subject? There is no need to analyze the sound. 
If you just want to measure noise level (dB values), you don't need to 
use the software. What is required is a device called the sound level meter 
(SLM) is enough. You can find a low price SLM around 80US$ on the web. For example, see http://www.contractor-books.com/EX/407730.htm

Our measurement software can be used to extend the function of SLM. For 
example, it can save measurement results, or perform the frequency analysis (octave band analysis). Note that SLM is necessary after all for measuring noise level even if you use the software. It is because the sound pressure level cannot be calibrated by the software alone. Acoustic calibrator can also be used for calibrating microphones, but it is more expensive than SLM. 

As for the software, we can propose three choices. First, RAL (24$) is 
recommended, if you prefer simple operation and you don't need to save 
numerical data. You can measure dB values using the 1/3 octave analysis. 
Results are displayed in a bar graph, and the sound level is displayed as a 
numerical value. 

Shortcoming of RAL is that it can measure the instantaneous sound pressure levels only. It means the display is always updated during the measurement. If necessary, the measurement results can be saved as a picture file by using Windows' screen copy function. But when you measure fluctuating sound, it may be difficult to follow the results. So, you should stop the measurement every time to check its sound level at a moment you like. 

Second is DSSF3 Light (83$). This is an upgraded version of RAL, and so it 
enables similar measurement. An advantage of DSSF3 Light is that the 
measurement data can be recorded (minimum interval for recording is 1 sec) during the measurement and then saved into a text file (CSV format). 

Third is to use the EA (Environmental noise Analyzer) module, that is 
available in RAE (83$) or DSSF3 Env (990$). EA's measurement screen is 
completely different. We can't see the frequency content of noise. Instead, 
the time history of the sound level is displayed. Measured data can be saved into a text file (CSV format) later. In addition, EA enables the automatic measurement by the level triggering. For example, if the trigger level is set to 60dB, only the noise exceeding 60dB will be measured automatically. This is a convenient function to monitor noise for a long period. 
 

[Back] [Up]


We have a analog channel in the cockpit in which we will be connecting our MIC and Pre amplifier. The data will be recorded in the magnetic tape and retrieved in the ground station. Is it possible to transfer our data in to your analysis software?
To transfer data recorded in the magnetic tape, possibly two solutions are available.

1) Connect the tape reader (player) to PC by use of line-in connector of PC or other audio interface. Then replay the data and record it in PC digitally by using the sound recorder of DSSF3 or other sound editor software. Save data in .wav format. Maximum data duration depends on the size of the hard disk. For example, 70 minutes stereo sound with the sampling rate of 44 kHz needs about 600 MB. The wav file can then be analyzed by our Realtime Analyzer or Environmental noise Analyzer.

2) Connect the tape reader to PC and replay the data (same procedure as above). Start the Realtime Analyzer to analyze the transferred data in real-time. It is almost the same as measuring sound coming from the microphone connected to PC. In this case, there is no limitation for the data duration because no sound data is stored in the hard disk. If you use Environmental noise Analyzer, the sound can be saved in the measurement database with the calculated acoustic parameters.
 

[Back] [Up]


I have a question about Data Record for the Octave Band function of
the FFT Analyzer.

The smallest Data Record interval allowed is 1 second. Is this 1
second interval a "window" in that it averages decibel values continuously
over the 1 second interval and outputs this average as the 1 second reading or does it take the decibel reading instantaneously at 1 second intervals?
The answer is it takes the decibel reading instantaneously at 1 second
intervals. The instantaneous data displayed on the graph is recorded at a given interval. Averaging data size is decided by the setting of the FFT
size, smoothing (time constant), and moving average. If you like to
record the averaged levels over 1 seconds, set the smoothing as 1s.
 

[Back] [Up]


Please tell me how smoothing and moving average affect the measurement results.
Smoothing and moving average affect the results if you measure the time
varying signals. Both will average the results, but their methods are
different: the smoothing is the exponentially weighted average, and the
moving average is the running mean. Practically, the smoothing is
recommended because it is same as the operation of the sound level meter
(i.e. its standard time constant is FAST: 125 ms and SLOW: 1s).
 

[Back] [Up]


Whenever I click on any of the main menu buttons (File, Tools, Window, or Help) the program crashes. I get the following error message: "RTA.exe has encountered a problem and needs to close. We are sorry for the inconvenience."
The same problem is reported to occur in other applications on Windows XP. It will be solved by setting the compatibility mode. Please try a solution reported in the following page.
http://support.microsoft.com/kb/326510/en-us
 

[Back] [Up]


 
Y Store.

| TOP | STORE | DSSF3 | Mmlib | Contact Us |