DOCUMENT:Q110881  13-JUN-2001  [winmisc]
TITLE   :Poor Sound Quality Using TrueSpeech Compression
PRODUCT :Miscellaneous Windows Products
PROD/VER:
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Windows Sound System, version 2.0 
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SUMMARY
=======

When playing a file compressed using the Windows Sound System TrueSpeech
compression scheme with the Turtle Beach MultiSound audio card, you may hear
popping or scratchy noises. This is due to a limitation of the audio card and
its Windows driver.

MORE INFORMATION
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There are currently two versions of the MultiSound Windows driver: 1.0 and 2.0.
Version 1.0 of this driver supports sampling frequencies of 11.025 kHz, 22.050
kHz, and 44.100 kHz. The TrueSpeech compression scheme, however, uses an 8.00
kHz sample that the driver does not support.

The range of sample frequencies in MultiSound Windows driver version 2.0 is
increased through a process known as frequency dithering. This allows the
MultiSound's built-in Digital Signal Processor (DSP) to contour the frequencies
into a more usable range by filling in the gaps. However, the process is not
compatible with the TrueSpeech compression method.

For further information about the Turtle Beach MultiSound audio card or the
availability of Windows drivers, contact Turtle Beach.

The MultiSound audio card and its Windows drivers are manufactured by a vendor
independent of Microsoft; we make no warranty, implied or otherwise, regarding
these products' performance or reliability.

Additional query words: 2.00 multi sound monterey play back record digital samples sampled

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Keywords          :  
Technology        : kbWinSoundSysSearch kbWinSoundSys200

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