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AU - Audio File

What is a AU file

The AU file was introduced by Sun Microsystems. This file format facilitates the storage of audio files, usually in three sections: a header with maximum strength of 24 bytes, an annotation block of variable length and the audio data itself. Primarily, this file format is used by Sun or other Unix-based machines, but it can be opened with various audio programs.

The AU format is associated with the µ-law logarithmic encoding that was endemic to the SPARCstation 1 hardware, where SunOS revealed the encoding to application programs through the /dev/audio interface.

Here's a small, but not exhaustive list of programs that can open AU documents:

  • Nullsoft Winamp
  • Apple QuickTime Player
  • Microsoft Windows Media Player
  • RealNetworks RealPlayer Cloud
  • Adobe Audition CC
About
Extension AU
MIME type audio/basic
Useful links