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File Format
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Description
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AIFF AIFC
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Audio Interchange File Format (AIFF)
Developed by Apple but
SGI uses it as well.
Filename extensions are .aiff and
.aif.
Files can be mono or stereo, 8-bit or 16-bit, and can be produced at many sampling rates.
The AIFC format is an extension of the AIFF format with file compression.
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AU
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Mu-law (m-law, AU)
This is the most common of the audio file formats.
It was designed for use in the telephone industry and has
wide cross-platform support.
The filename extension is .au.
The file format is mono only, 8-bit, at 8KHz sample rate, which
produces relatively poor quality monaural sound with much
more hiss and crackle than other sound formats.
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MIDI
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Musical Instrument Digital Interface (MIDI)
MIDI files are not actually recorded sound like other formats but
synthesized sound.
MIDI files consist of simple text instructions to the microcomputer
sound card MIDI interface that allow it to play sounds using a limited
palette of simulated or sampled musical instruments and sound effects.
MIDI files are much smaller than recorded audio files because they
consist only of instructions rather than a recorded performance.
The filename extension is .mid.
The quality of the sound produced is dependent on the quality of the sound
card and the MIDI sound palette or scheme available on the microcomputer.
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MPEG
MPG
MP2
MP3
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Motion Picture Experts Group (MPEG)
MPEG files can contain CD quality audio and video.
They require that the microcomputer have a good decoder installed,
usually a browser plug-in. MPEG files can be large, depending
on the degree of compression and sampling rate, but are generally
much smaller than WAVE files.
Filename extensions are .mpeg,
.mpg,
.mp2 and
.mp3.
The quality of the audio playback is determined
not only by the sophistication of the decoder used but also by the
sampling rate at with the sound was encoded, and the degree of file compression.
For a full description of the MPEG file format with instructions on recording, editing
and sources see The Official FAQ for alt.binaries.sounds.mp3.
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WAVE
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WAVE (for the audio wave form)
The WAVE audio file format was developed by Microsoft and IBM
for transmission of CD quality sound over the Internet.
The file format is similar in construction to the AIFF format.
WAVE files are very large. File size depends on the length of
the recorded performance and on the sampling rate used to record and
encode the audio information for playback.
Playback support for WAVE files is generally built into browsers and generally
does not require plug-ins. The standard Windows media player and sound
recorder can be used to play and record WAVE files, respectively.
The filename extension is
.wav.
The quality of WAVE files depends largely on the sampling rate.
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Audio
