AC3 Filter 2.6.0b

High quality freeware DirectShow audio decoder and processor filter used to decode audio tracks in movies.

Note: We've detected that AC3 Filter's installer might attempt to bundle third-party software. We suggest to proceed with caution and select the "Custom" installation option to identify any potential unwanted software.
4.0 MB
4.8 38 votes

AC3 Filter can decode following audio formats: AC3 / DTS / MPEG Audio. It also supports multi*channel and digital (SPDIF) outputs.


  • Decode AC3/DTS/MPEG Audio Layer I/II formats
  • MPEG1/2 PES demultiplex (for DVD support)
  • PES/LPCM format support
  • AVI/AC3, AVI/DTS, WAV/AC3 and WAV/DTS support
  • AC3/DTS/MPEG Audio SPDIF passthrough support
  • AC3 encode to output any multichannel source to SPDIF
  • Detailed input bitstream format information
  • Automatic Gain Control
  • Dynamic Range Compression
  • Online output configuraion change
  • Upmix from any stereo source to 3*6 channels
  • Downmix to DolbySurround/ProLogic/ProLogic2
  • Input/output levels indication
  • Per*channel gain for all input/output channels
  • Per*channel delays
  • Direct access to mixing matrix


  • Audio Codec Tag 2000 may be requested when AC3 Filter is missing.
  • Audio Codec Tag 8192 may be requested when AC3 Filter is missing.
  • It also solves AC3 DVM codec missing, reported by AVIcodec utility.

What's New:

  • FFMPEG updated to v1.1.4
  • Use FFMPEG for AAC decoding (should be less crashes because faad bugs).
  • SPDIF/AC3 encoder: encode 5.1 with back channels (used by flac for instance) like 5.1 with side channels (standard for ac3).
  • Serbian language added (thanks to Rancher).
  • Languages updated: Basque (thanks to Xabier Aramendi), Chineese (thanks to PoYang).
  • Bug fixed: some languages was reset to english after restart.
  • Installer: /noicons option works now