@james: some nice ideas, though i don't see much advantage in having a quad vca when two dual vca's will do just the same and be just as small. the normalizing to all inputs is a good idea. or at least designing the circuit board to allow this as a simple modification - i am constantly frustrated by sockets that are double soldered onto the board, making normalization impossible.
@nick: with respect, my intention in assembling a polyphonic modular synth is not to reproduce the architecture/sounds of any polysynth that already exists, but quite the opposite. the mono sounds i use on stage cannot be produced by an ms20, minimoog or any other monosynth, and this is what i would like to adapt to polyphony. slightly different version of a sound for each voice is only the beginning. am/ring modulation and fm between different voices produces a lively changing spectrum even from a repeated major chord (i've tried all this struggling with multiple keyboards/a190's)
the main disadvantage of a modular poly setup seems to be the amount of twiddling that needs to be done to change a voice to something specific, "i'm feeling lucky" twiddling not withstanding. i have found two a155 sequencers quite convenient as an 8 preset bank, using the gate outs to apply routing changes and the cv outs to set values of critical bits. but this is an expensive and rack-consuming experiment not really worth lugging onstage.
polyphonic modulars are de facto non-existant in the "mainstream" of electronic music. dieter's unbeatable price/quality relationship makes it a safe bet that when polys do finally make their presence felt, we'll be seeing the doepfer name all over them.
and mine too, if nobody else does those quad modules :)
stu