[net.micro] Built-in Music Chips--So What?

knudsen@ihwpt.UUCP (mike knudsen) (10/18/85)

As someone who has done quite a bit of computer music synthesis
programming, I've come to believe that the sound chips built into
a home computer are ultimately irrelevant.
	By that I mean that for games and beginning music hackers,
the three or four musical parts (voices) provided will be OK.
You can do a lot with 4-part harmony, or even 3-part plus
percussion.
	But as you get serious, you find that you need
more parts than the built-in hardware and software support;
plus you want more sound qualities (timbres), and ADSR
envelopes, etc etc.
	With the exception of that MSX Yamaha Z-80 machine
with the built-in FM chips, NO computer on (or about to hit)
the market provides enough hardware/firmware up front.
Check out (and correct, please) this list:

Atari800	4 parts, some timbre control
Commo64		3 parts+percussion, "
Mac		4 parts, total timbre control (waveform tables)
Amiga		like Mac, with more HW support and some patching
ST		3 parts + percussion (GI 8910, ancient, OK for games)
Apple][, IBM PC	1 part beep, no volume nor timbre -- joke city!
TRS CoCo	1 part, control of volume but not timbre (BASIC)
TRS CoCo	4-8 parts, total timbre control (like Mac, Amiga)
TRS CoCo	1-2 parts, FM synthesis with ADSR

Okay, I listed my trusty Coco 3 times for a reason.
It has a built-in D-A converter that outputs to your TV
any sound you can conceive and compute fast enuf.
The built-in BASIC does only one square wave with volume control.
But my own software, and some commercial packages,
support 4 parts with user-defined waveforms much like
a super Hammond organ.  I can easily extend mine to 6-8 parts
by accepting a lower sampling rate.
And I have written an FM synth that I play from the keys
and can "bend" the timbre and volume within a note with
the joystick.
	So--does "the Coco have FM?"  Does "the Coco have
8 parts, infinite timbres?"  Well, it has a D-A and some hackers
willing to write some tight assembler code.
	The Mac, Amiga, and ST are all believed to contain
8-bit D-As.  Use whatever built-in hardware (DMA, etc) to help
you write code, and you too can sound as good as a Coco.  Better!

	But software synthesis can go only so far.
Now you must ask "what kind of peripheral synth'ers can I buy/build
to plug into my computer?"  Apple][ has the Mockingboard
and Syntauri; Coco has Symphony-12; etc.  Did Apple really do
musicians a favor by putting almost nothing in the ][ series?
	Still not satisfied?  Get a MIDI interface
(all new machines and the Coco have these available, cheap).
Then the sky's the limit -- or should I say your wallet?

To summarize -- built-in music chips are like the built-in
RAM and disk drive -- no matter how good they are, you'll
want to add more.  But, unlike existing RAM and disks, the music
chips will probably sit unused once you upgrade.
	So why not just ignore the built-in music chips in
the first place, if the rest of the machine has what you want?

	--mike k