c64-2-synth hack

[tomg]

I dig out my old c64 and started playing around with the SID or
6581 Sound Interface Device. This is one cool chip. I remember
something about a couple of guys working to get an interface and 
midi connected to this and thought I might try it. I have 2-3 6581s
and c64s are $3-5 bucks in the thrifts around here or they are as
of this posting. If it goes the way it has been I'll never see another
one now...;-) BTW only the old humpy tan-c64s will work for pulling
SIDs. The newer low-profile have SMD SIDs. They can be used for 
the c64-2-synth hack though. The dip SID is a 28 pin device.

I have a short basic/ml program that scrambles the 6581s registers.
It comes up with some unbelievable sounds. If you find one you
like it can be saved to disk and reloaded. I just got'a do an mp3
for you guys! It also converts the c64-kbd to a musical form of
sorts. I don't think it would be hard to tap in and connect a small
three-oct kbd, C64-2-Synth hack. What would be neet is if some-
body had a way to get this proggy on a c64-cart! Old rom burner
anybody?  

I have the specs and some app-notes, like the register-map and
a pin-by-pin description. Anybody interested in helping? I don't know 
where I'm going to squeeze this in but I will find time! It's too cool
to ignore.

3 Tone Oscillators, 0-4K ,tri/saw/var-pulse/noise ,sync ,glide
3 Amplitude Modulators, 48dB
3 Envelope Generators, A:2ms-8s,D:6ms-24s,S:0-PeakVol,R:6ms-24s
Ring Modulation
Programmable Resonance Filter, 30Hz-12K 12dB/oct, high/low/band/notch/high
Master Vol
2 A/D pot interfaces
Random number/Mod Generator
External audio input.

tg