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Windows: How to determine your audio card's, or USB mic's, maximum sampling rate
User: kmaclean
Date: 1/1/2010 12:10 pm
Views: 46980
Rating: -24

To submit audio to VoxForge, You need to make sure you Sound Card and your Device driver both support a 48kHz sampling at 16 bits per sample. 

You can use SoundCheck from Passmark software. It is proprietary but has a 30 day trial period.  

1. Audio Device Driver - max rates

After you download and install Soundcheck, you can determine the maximum sampling rate and bits per sample of your audio device driver supports by clicking the following in Soundcheck's main menu:

Settings>View Wave Capabilities - Windows 

The "Device Capabilities" window will pop-up.  Make sure "Select I/O' is set to "Input", and that you have the correct "Device" (if you don't know, use the default).  Next, look at the "Formats sound card driver claims to support" section and scroll down to the bottom of the list to see the max rates your audio driver supports.  

I have the "Realtek AC97 Audio" Driver installed and the max recording (i.e. Input) rates that it supports are as follows:

 ----Basic Formats -----

[...] 

128.0kHz, stereo, 32-bit - Ye

2. Sound Card - max rates

To confirm that your sound card also supports a 48kHz sampling rate at 16bits per sample you need to record some audio - your voice will do fine for this test.

In the "Sound format" section of Soundcheck's main window, select the following settings:

Requested Sample Rate: 48000Hz (DAT Tape)

Channels: 1 (Mono)

Resolution: 16 bit 

In the Data rates (Bytes/Sec) note the values in these fields:

Requested: 96000 

Actual In:          (blank)

Average In:          (blank) 

Next, Record (click the circle icon on bottom left of SoundCheck Window) yourself speaking a sentence with no pauses for about 3 seconds.  If the value in "Average In" matches the Requested value (by around +-5%), then your hardware supports recording at a 48kHz sampling rate at 16 bits per sample.

I recorded myself saying "this is a test" and got the following values:

Requested: 96000 

Actual In: 97901

Average In: 95358 (-0.67%)

I am still looking for an Open Source Solution to determine a sound card's (or USB Mic's) maximum sample rate and bits per sample.  Please let me know if you come across one.

Re: Windows: How to determine your audio card's, or USB mic's, maximum sampling rate
User: kmaclean
Date: 10/31/2010 9:57 am
Views: 757
Rating: 23

more info here: Playing with Webcam USB mic

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