User Guide

APPENDIX E
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APPENDIX E:
SOUND FORGE XP AND
THE MICROSOFT AUDIO
COMPRESSION MANAGER
THE AUDIO COMPRESSION MANAGER (ACM)
The Microsoft Audio Compression Manager (more commonly referred to as the ACM)
is a standard interface for audio compression and filtering tool in Windows.
This interface allows applications like Sound Forge XP to use compression and
filtering algorithms provided by other companies.
Sound Forge XP fully supports audio compression and filtering through the
ACM. This enables you to use any ACM-compatible compression and filter
driver.The best part of this support is you don’t have to learn anything new to
use it! Sound Forge XP transparently opens compressed WAV files and provides
all available compression formats for WAV files in the Save As dialog (File
menu). No Import or Export commands are necessary.
There are roughly three pieces to the ACM (though these pieces are tightly
coupled). It is not necessary for you to know any details about these pieces to
use the ACM from Sound Forge XP, so this information is supplied for those
who want to know more.The three pieces of the ACM are:
• Audio data compression and decompression
• Audio data filtering (Digital Signal Processing)
• Transparent playback and recording of non-hardware supported audio files
AUDIO DATA COMPRESSION AND DECOMPRESSION
The first piece of the ACM allows you to compress and decompress audio data.
Audio compression is used to decrease the amount of data required to
represent a sound; this ultimately results in smaller sound files. However, there
are drawbacks to using audio compression on your sound files: