MOTM Status Report

Kurt Dwight Bleach gghegel at
Tue Dec 23 06:30:34 CET 1997

I guess I missed the original post(s) because I'm not sure what MOTM
means, but it sounds incredibly interesting--especially since I spend at
least half of my DIY effort making front panels, which just really isn't
that much fun.

All of the modules you describe sound great. I don't know if you're
taking advance orders, but I'd certainly like to be counted in!!

Are you taking suggestions for other modules? If so, here's mine:

I'd love to have some kind of "universal" transformer/multiple module. I
was actually tinkering around with some ideas for this, but
unfortunately the electronics involved are out of my (very basic)
league. However, I think it could be loosely based on the Digisound 80-5
processor, which has a lag processor and then four multiple-type groups,
each with an input, an attenuator and four outputs. The first two also
feature an "inverted" input, wherein whatever you input is inverted at
the output. It would be great to add an exp/lin converter/multiple with
an attenuator, and a lin/exp converter/multiple with an attenuator, for
those of us who have combinations of instruments that aren't completely

So, the device could be set up something like this:

Top row--     Lag processor: One input; attenuator; two outputs.
Second row--     Multiple : Two inputs; attenuator; two regular outs;
two inv. outs. {Hopefully this would be designed to correctly transform
triggers from Korg type to Moog type--I can't remember which is which at
the moment.}
Third row---     Converter 1: Two exponential CV inputs; attenuator; two
(summed) exp cv outs; two linear cv outs (inputs summed before
Fourth row--     Converter 2: Two linear CV inputer; attenuator; two
(summed) line cv outs; two exp cv outs (inputs summed before
And then, what the hell, how about a row of straight multiples at the

Anyway, that's a module I'd love to have, although I'm probably
completely talking out my butt because the exp/lin conversion (and/or
vice versa) might be too difficult to justify sticking in this kind of
"universal" module. And maybe a bit too esoteric--anybody else dumb
enough to base their studio on mis-matched gear? (The Paia stuff I could
probably do without, but I'm not giving up my MS-20, dammit!! And I'd
love to let it be able to "grove" with my other toys.)

My other suggestion would be a very simple, cost effective 8 step
sequencer, groups of which could hopefully somehow be chained together.

Anyway, those are my little pie-in-the-sky ramblings. But since I don't
have any schematics to contribute, I'll just shut up and look forward to
the modules you're already working on...

Paul Schreiber wrote:

> Since the gum surgery is all over, the stiches are out, and I get all
> next week off, it's MOTM Time!!
> 1) I got a decent price for the front panels. So, I will offer black
> anodized, white lettered panels. THey
> are either 2U or 3U wide and 5U tall. Also, blank 3U wide ones.
> 2) I will offer "stringer" brackets for 19" racks. You screw these
> across 5U apart, and the modules bolt to that.
> The only issue is power supply distribution, but an enterprising
> person can buy a Elpac WM220-1 power
> supply, and a blank panel, and a 5 pin DIN, and be all set!
> 3) About 9 of you are "really thinking hard" for the wood case, so
> that's what I'm planning for (plus mine!).
> 4) I have begun to order the parts for #1 and #2. Here is the run-down
> for the 2 modules:
> #1
> Low distortion Ring Mod - designed by Thomas Henry & Paul S. Uses 1/2
> of a CEM3330, OP275GP ultra-low
> noise op amps
> AGC's Noise source - designed by Dave Rossum of EMu. Discrete
> transistor/FET design. Plus a TL074ACN.
> Precision S&H - uses National LF398AN for 1mv/sec droop, 1mv offset.
> Has simple internal clock, or
> external clock. Has lag adjustment.
> Ultra-low-noise/distortion mic preamp - uses Burr Brown INA103 with an
> AD820AN DC servo amp. No caps
> in the audio path. <.005% THD+noise. XLR input.
> Compressor/limiter - can be used with mic pre-amp or stand-alone.
> Variable knee, compression ratio.
> Simple VCA - where the other half of the 3330 went to!!
> The cost (not final) should be around $130/$120 with cabinet (cabinet
> folks ALWAYS get a discount!!)
> #2
> Stereo synthesizer - mono IN, stereo OUT. Kind of cute. Possible Wide
> Field stereo expander mode
> if I can address patent issues.
> "Clickless" analog switch - set up as 2ea 2:1 muxes. Voltage
> controlled switch points!
> DC switch - same as above, but for CVs. Uses precision DG213DJ switch
> (none of that cheesy 4066 stuff!!)
> Cross-Product Module - Bernie Hutchins/Thomas Henry's basic design 1
> step farther. This can be used as
> a stand-alone sub-octave divider, or with 2 inputs it generates the
> most bizarre timbres ever. Hard to describe.
> Build it and see!! Great for drones/goa stuff. Very weird. Lots of
> knobs.
> Also, around $120/$105.
> I expect around Feb. 10th for both of these to be ready to immediate
> delivery. As always, comments/feedback
> welcome.
> What will the rest be? Well, assuming I sell THESE first (ahem!), they
> are:
> #3 Dual 3340 (<<<not a typo) VCO
> #4 Quad VCA
> #5 Dual VC EG w/delay
> #6 15-mode Xpander fiter
> Happy Holidays!!
> Paul Schreiber
> Synthesis Technology

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