[sdiy] Radfio Shack

[Fredrik Carlqvist]

>Hybrid systems would be interesting, analog sound with
>digital control.

I'm doing hybrid systems. If anyone is interested, here's my setup:

I use one simple microcontroller (PIC) to replace the VCO, LFO, ENV, MIDI,
and interface parts of a standard synth setup. Outside it, I have a PS, a
ramp generator, a VCA and a VCF. They are controlled using a 16-bit DAC.
Basically this is the same setup as in a Moog Source, but on an entirely
different scale. (also, I have several pots, not one 'dial')

So the sound chain is more or less analog, but with minimum part count. And
I can save my patches. 

The things that are hard to do in software, I put in hardware. The things
that are hard to do in hardware, I do in software. No hard to get parts
(well, before the discontinuation of CA3080 that is), no expensive parts and
full control!

I get maximum control over the CVs, since I can reprogram the micro (via
MIDI) to do whatever I want. I don't get any alias problems, since the
oscillator is more or less analog. I don't have to do any heavy numeric
stuff to simulate a 4-pole filter, because the filter is in hardware. No
tempcos, because the quartz crystal that times the oscillator don't drift. I
can switch on and off the oscillator jitter. And it all fits on one 7.5x10
cm board (3 by 4 inch for you Americans). Without SMT (except the farging
MSOP8 DAC, gaaahhh!). 

Fredrik C