Article 21737 of comp.sys.atari.st:
Path: mucs!ukc!mcsun!uunet!aplcen!samsung!cs.utexas.edu!sun-barr!newstop!sun!imagen!atari!apratt
From: apratt@atari.UUCP (Allan Pratt)
Newsgroups: comp.sys.atari.st
Subject: Re: Atari STE Sound chips
Message-ID: <2062@atari.UUCP>
Date: 1 Mar 90 19:46:57 GMT
References: <1990Feb24.222700.22004@newcastle.ac.uk> <729@duteca.UUCP> <1990Feb28.195455.17049@chaos.cs.brandeis.edu>
Organization: Atari Corp., Sunnyvale CA
Lines: 39

topgun@chaos.cs.brandeis.edu (Chandra Bajpai) writes:
>What type of sound chip does the STE use? Is it different from the ST?
>Does the quality of the sound chip rival that of the Mac II/NeXT/Amiga?

The STe has two sound subsystems.  One is like the ST's: it's a Yamaha
PSG (Programmable Sound Generator), also available from General
Instruments (I think), which is why you see it referred to as "The PSG"
and "The GI Sound Chip."

The other sound subsystem in the STe is our own creation: it's a
two-channel 8-bit digital-to-analog converter which is fed by DMA
(direct memory access), which means the processor can set it up and
then go do something else while it's playing.  You will hear that
referred to as "digital sound" or "DMA sound."  Data goes to the DAC at
50KHz, 25KHz, 12.5KHz, or 6.25KHz, selected in software.  There are two
channels, one left and one right.  You can play monaural sound out BOTH
speakers and use only half the data.

The quality is very good.  I don't know how to quantify that. Remember
that digital sound is only as good as your sampler plus your playback
(including amp and speakers), and the STe serves as part of the playback
system: you provide the amp and speakers.  The sound will come out
the monitor's speaker, but that's not stereo and it's just not up
to the task.

The NeXT box has a DSP (digital signal processor), which doesn't just
play back sound, it GENERATES it from formulas or other data. That's a
different beast altogether.  Amiga's the same way.  I guess those chips
can simply play a sampled sound, and I don't know how to compare them
against the STe's sound capability.  The STe is certainly better than
the Mac's digital-sound-output mode: the (highest) sampling rate is
higher and we use better filters to smooth out the "jaggies."

For more technical specs you'll have to write to Atari; I don't
know anything about audio electronics.

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Opinions expressed above do not necessarily	-- Allan Pratt, Atari Corp.
reflect those of Atari Corp. or anyone else.	  ...ames!atari!apratt