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Archived - Macintosh: Sound Capabilities (9/94)
The following article provides information on a variety of topics relating to audio and the Macintosh.
http://support.apple.com/kb/TA32601
Mac Plus, SE, Classic
8-bit mono sound to one channel (you'll hear only one side with stereo headphones, unless you use an adapter)
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Performa 200, Performa 400-467 (not 47x), Classic II, LC II
Mixed 8-bit mono sound to both channels (you'll hear sound out of both sides with stereo headphones, but the sound won't be true stereo)
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Performa 475, 476, LC 475, Quadra 605
Stereo 8-bit sound, including true stereo from non-audio CD's (connected externally). Audio CD's require external speakers, enhanced Apple Sound Chip supports stereo.
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Performa 5xx, 63x, LC 5xx, 630, Quadra 630
Stereo 8-bit sound, including true stereo from audio and non-audio CD's (Enhanced Apple Sound Chip supports stereo).
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Performa 600, 600CD except Mac IIvx
Mixed 8-bit mono sound to both channels, except true stereo from audio CD's (No ASIC to support stereo from software)
Among desktop Macintosh computers, only the 660AV, 840AV, and Power Macintosh models have 16-bit audio input and output capability because of the AT&T DSP3210 hardware circuitry and the 16-bit Singer codec circuitry in the AVs. The Audio Waveform Amplifier and Converter (AWAC) chip in the Power Macintosh performs the same 16-bit I/O functionality. The PowerBook 500 series computers support 16-bit stereo output, but only mono input.
Kind of interesting about the Apple IIgs:
http://en.wikipedia.org/wiki/Apple_IIGS#Audio_features
Audio features[edit]
The Apple IIGS' sound was provided by an Ensoniq ES5503 DOC wavetable sound chip, the same chip used in Ensoniq Mirage and Ensoniq ESQ-1 professional-grade synthesizers. The chip allowed for 32 separate channels of sound, though most software paired them into 16 stereo voices, as did most of the standard tools of the operating system (the MIDISynth Tool Set grouped four channels per voice, for a limit of seven-voice audio). The IIGS is often referred to as a "fifteen-voice system," because one stereo voice is reserved by the OS at all times for timing and system sounds. Software that doesn't use the OS, or uses custom-programmed tools (most games and demos do this), can access the chip directly and take advantage of all 32 voices.
The computer's audio capabilities were given as the primary reason for record label Apple Corps's 1989 resumption of legal action against Apple that had been previously suspended. Apple Corps claimed that the IIgs' audio chip violated terms of the 1981 settlement with the company that prohibited Apple, Inc. from getting involved in the music business.
A standard 1⁄8-inch headphone jack was provided on the back of the case, and standard stereo computer speakers could be attached there. However, it provided only mono sound through this jack, and a third-party adapter card was required to produce true two-channel stereo,[7] despite the fact that the Ensoniq and virtually all native software produced stereo audio (stereo audio was essentially built into the machine, but had to be de-multiplexed by third-party cards). Applied Engineering's SonicBlaster was one of a few developed cards for this purpose.
More about the Macintosh Portable and IIci Sound Features
http://tech-insider.org/mac/research/1989/0920.html
- Apple Stereo Sound capability: The Portable features
the same high-quality digital sound capabilities as found
in the Macintosh modular line and in the SE/30.