vc wave select

[jh]

I don't want flame wars on synth-diy, so don't consider
the following statements as "against" anybody -they are
not.

I think everybody has his own preferences and style of
circuit design, and I love to see various approaches to
achieve certain functions. I like the idea of having the pure
waveforms first and the combined ones later, though personally
I would prefer a set of push buttons with LEDs for selection
of individual waveforms or combinations of waveforms (press
several buttons at the same time for multiple waveforms).
For manual selection, that is. For voltage control, I would not
use switching at all, but crossfading.
But sometimes I'd come to solutions that I would not have used
in the fist place, because of other constraints. For my HiFli
clone, I wanted to have push buttons for modulation waveshape
selection, but I did not have the front panel space. So in the end
I used rotary switches, but I combined them with LEDs, so that
I had a "list" of modes printed on the front panel with a LED
at the beginning of each item, and the rotary switch controlling
these LEDs. 
For external CV routing, I even went one step further. I had one
green LED next to each CV-able potentiometer (distributed
all over the front panel), plus one central knob to select the CV
routing. I considered a potentiometer + ADC solution at some point,
but then I chose a rotary switch plus LEDs. Rotary switches are
so cheap and easy to handle.
My point is that I do *not* like it better than the original EMS solution
(which is hard to beat, really !) - but I think it was a good compromise
for the 2 U 19" front panel I had chosen. I really loved it in the end.


As for the Moog ladder being complicated, I don't think so.
Only Korg would have be able to build a 4-pole filter with lower transistor
count (;->). But seriously: Most (all?) other VCFs have a higher
transistor count. They are just hidden inside 3900's or 3080's.
Many people shy back from my 2040-like filter because of the transistor
count, for example. But hey, these otas are (deliberately) built from
*less* transistors than a 3080 contains ! So the Moog ladder is
truely brilliant for its *low* transistor count (amongst other reasons).
The SSM 2044 (not 2040 this time (;->) ) should be a close second
I suppose, but I did not really count ... 

JH.