AC-3 ACM Codec 2.2
AC-3 ACM Codec (formerly AC-3 ACM Decompressor) offers Dolby Digital AC-3 decoding for Windows ACM. Install this and you can convert/decompress AC3 audio directly to WAV / MP3 using VirtualDub. This also works with AviSynth, TMPGEnc, allowing you to use AC3 encoded AVI files, not normally recognised.
Freeware
Changes in AC-3 ACM Codec 2.2:- By request the x86 version now works on Windows 95 OSR2 and Windows NT 4.
- Fixed an uninstall problem specific to 64-bit Windows.
- Added experimental support for tag WAVE_FORMAT_EXTENSIBLE.
http://fcchandler.home.comcast.net/AC3ACM