[net.micro.atari] ST Sound Chip Is AY-3-8910? YUCK!

c160-3ay@ucbzooey.BERKELEY.EDU (Ranjit Bhatnagar) (10/14/85)

( Put this in your pipe and smoke it, Line Eater. )

Warning: almost-flame---

I'm sorry my previous message turned out blank.  Here it is again:

Thanks to those of you who responded to my query about the ST sound chip!
However, I was dismayed when I learned that it is an AY-3-8910.  I have
used this (or similar) chip for several years in peripherals for my Apple.
It is better than what's built in to the Apple, but for Atari it's a step
backwards.  The Atari 800 Pokey chip was definitely much better.

	Pokey				AY-3-8910
	4 voices			3 voices
	or 2 voices with 65536          only 4096 frequencies
	  possible frequencies
	programmable waveform           icky square waves only
	  (with some difficulty)

After reading about the Amiga with FM synthesis, and playing with a Mac with
completely programmable waveforms and 4 voices, I was depressed to see that
the ST chip could produce only square waves.  

Since it produces only square waves, the 8910 can not make realistic or
pleasant sounds.  Since it has only 4096 possible "tone periods", high
pitched notes are inherently out of tune.  The white noise generator is
not random enough- you can sometimes hear tones in it.  The built-in
envelope generator is handy when you are first learning to use the 8910,
but its envelopes turn out not to be very useful in general- the shapes
are not natural, and they can only be applied to all 3 voices together.
Happily, it is possible to manually produce any envelope by changing the
amplitude parameters "on the fly".  With only 16 possible amplitudes, 
you can hear the steps in volume as a note decays slowly.  

In summary: the 8910 is easy to use but not at all suitable for music or
realistic/natural sounds.

I may have some tutorial articles that I wrote on programming the 8910
on a disk somewhere... I will post or mail them if anyone's interested.
They are intended for the Apple Mockingboard, but the same concepts apply.

I hope that someone comes out with a cheap MIDI device which is to the ST
what the Mockinboard was to the Apple... becoming a defacto standard for
better sound effects so programmers will have something nice to work with.
If it's not cheap enough, nobody will buy it and programmers won't bother.
On the other hand, it must be good enough to be worthwhile (at LEAST 
should have programmable waveforms) and good enough that it does not have
any competition- competition would ruin the possibility of a standard for
ST sound appearing quickly.

......Ranjit Bhatnagar   (hoping to buy an ST or Amiga soon!)

kek@mgweed.UUCP (Kit Kimes) (10/14/85)

Remember, ATARI is trying to shed the 'game machine' image.  I believe
they deliberately avoided the sprites (not needed anyway) and super
sound to show they are serious about producing a machine that will be
considered for business and other serious applications.  I think this
will hurt a little bit when they bring out the 260STD because that 
machine will be bought primarily for people to use at home and they
will want to play games and have great sound.  Only time will tell.
 
					Kit Kimes
					AT&T Information Systems
					Montgomery Works
					Montgomery, Il. 60538-0305
					..!ihnp4!mgweed!kek