Theremin as synthesiser controller

Hey
check out this DIY CV to Midi converter (http://tomscarff.110mb.com/cv2midi/cv2midi.htm)
Ive built one of these but have only used it with other synth stuff- havent added cv outs to any of my EWs yet so I cant say how well it performs with theremin...however it sends pitch and volume data and The EWplus is mentioned in the description (bottom of page)-so Id assume it works well.

If you do want to delve into the world of DIY synth,(watch out its a slippery slope) MFOS is an excellent place to start. If you already have some experience building electronics , Id recommend either the "sound lab plus" or "ultimate." I built a SL + and its very cool- its not a Moog, but is not a toy for fx either. Good 1v/ octave tuning. My only regret is the timing of my build- the Ultimate came out just as I was finishing up the SL+.
Some other great places are Yusynth.net (http://yusynth.net/Modular/index_en.html) and http://www.cgs.synth.net. A bit more advanced but tons of cool circuits.

What is "MFOS", if you please?

[edit] Nevermind! MFOS = Music From Outer Space (http://www.musicfromouterspace.com/mfosweb/home.action)

i suppose i'm entering this conversation a bit late in the game, but i have been looking for inexpensive CV voices for the e-plus also -

at first i was working a lot with the ~$350 moogerfooger freqbox, which contains a VCO (sweepable between sawtooth, triangle, square, pulse) as well as an envelope follower, (and also the ability to FM modulate the theremin's own sound with the VCO, or mix the theremin's voice and the VCO set to, say, an octave up or down or whatever).

here (http://www.youtube.com/watch?v=cKCgSKx8jWY) is an old demo i posted of it, pls excuse the horrible intonation and sound quality...

unfortunately, you will find that once you leave the triangle mode, it really starts to need a good filter...

i also tried a korg monotron (~60) which contains a VCO (sawtooth only) and a -great- sounding VCF (i am told very similar to the korg MS10). it is fairly easily modifiable to take CV inputs. HOWEVER i ran into two main problems - i couldn't figure out how to get rid of the horrible noise that is on the monotron's only output (a headphone output), AND it has a really horrible envelope - basically "on and off" (with some extremely limited fake-enveloping possibilities by using the monotron's lfo on the filter). so, because of the noisy output and the on/off envelope, it is not a great solution.

this sent me spiralling into looking at all sorts of modular gear, because i have this irrational love for modular gear like a moth to flame... after a brief foray into analogue systems gear (which is nice, but EXPENSIVE (especially because of the exchange rate i imagine))...

..i found this guy who is SUPER SUPER NICE: Mattson Mini Modular (http://www.mattsonminimodular.com). for roughly the price of a new moog analog synth, you could have a pretty good start on a real modular system... uh. well i guess roughly speaking for the price of a little phatty you would be able to afford a mattson custom walnut case, envelope follower, VCO, VCA VCF,... i guess that's about it, but it covers a lot of territory. the plus side of this is that (a) you would have an awesome looking, super expandable real modular synth. the minus side (vs. the little phatty) is not having savable patches, an LFO (that module would make it more expensive than the little phatty i think), and a keyboard... but people like us don't need keyboards, now do we???

also, mr. mattson might be able to be convinced, i think, to do a combo euro-rack and mattson format case, which will open you up to a whole giant world of modular madness, sigh.

random wendy carlos-esque video (http://www.youtube.com/watch?v=SY2ijf1nJPk) of a mattson modular

i am receiving a sort of beginner's mattson case in a bit i will try to post a video or something..

edit: oops i see now that there is a quite reasonably priced moog "slim phatty"... $800.. that is pretty nice, actually...

That Mattson Mini Modular (http://www.mattsonminimodular.com/) Does look interesting - (note - your link doesnt work.. you need to include the http:// or I think TW tries to obtain the URL as an extension of its home page)..

But, as you say, at $800 ish, the Moog Slim Phatty does look hard to beat! - Particularly if you are want to use it for more than just theremins.. It looks like a great analogue MIDI expander.

I do not know if it would be possible to drive the Phatty from a MIDI sequencer and use the CV inputs simultaneously from a Theremin - Cant see why not...

Fred

oops thanks fred! fixed the link...

yeah i wrote that whole thing under the pretense that at ~$1250 for the little phatty, you might as well start a modular system... but i feel like at $800 the slim phatty is so nice an compact and portable that it seems like a pretty sweet option for a theremin player. one thing i was wondering, in case anybody knows - with most analog systems, you have to tune the oscillators for temperature variations, operating temperature, etc.. with the new moogs synths, do you still have to "tune" the oscillators or is there some sort of new-fangled crystal set circuitry that keeps it stable?

if you are planning on mixing both the outputs of the theremin and the outputs of whatever analog synth, sometimes it can be a bit painstaking (e.g., if you are in a cacaphonous environment) as first you have to tune them at some base note and then you have to go high and tune the synth's scale response, and then go back to the low note and repeat that cycle a couple times...

ALL THAT being said, i love the mattson system because:

1. it is a super compact modular system - if you look at a moog format modular, there ends up being a lot of "air" in the case. to a similar (but lesser) degree, the same is true of euro-rack systems. (although this won't be true if you ask him to make you a combo mattson/euro case, in which case there will be plenty of air)

2. he cuts costs in ways that make sense to me - the metal faceplates are "standardized" (e.g., like a 4x4 matrix of holes) and then durable plastic panel graphics are applied, which is more economical (and in my opinion looks great) than screen-printing a different steel panel for each module. the "knobs" are just rubber sleeves on the potentiometer shafts, which makes sense and works (in that format most real "knobs" would be too big anyway)... he "recycles" the left-over laser cut steel from his case rails to make other things, like combs for "cable caddies"

3. the guy is the nicest, most responsive analog synth manufacturer i have met, (don't get me wrong, other people are great too but just don't seem to be so responsive and receptive to custom ideas).

4. you will look like a mad scientist setting up a modular system for your theremin when you perform!

PS i think you can use the MIDI and CV inputs on the little phatty simultaneously, but the result might be chaotic since it is a monophonic synth i think... so like i guess it would be spitting out a CV for your midi note and adding the CV from your theremin and giving you whatever higher pitch is the result...?

PPS - also that mattson guy will sell his modules in a "do it yourself format" for much cheaper - i believe they are about ~$80 (depending on which module) for a tested board, but you have to figure out the jack connections and pots yourself...

[i]"do you still have to "tune" the oscillators or is there some sort of new-fangled crystal set circuitry that keeps it stable?"[/i]

LOL! ;-) IMHO, there has always been only one way to get 'good enough' thermal stability from the exponential converters.. and this is by 'ovening' the transistors in the exponentiator.. Most synths get away with using a temperature compensating resistor (tempco) and physically coupled transistors - this used to be a cheaper, nearly good-enough option - I think the Moog Source was the first 'low cost' synth to fully 'oven' the transistors (may be wrong..)

Looking at recent Moog Circuitry, I would be extremely surprised if there was any drift or tuning problems with the Phatty. This is the technology Moog pioneered and advanced way above any other - it pervades all Moog products - And ovening is even used in the exponentiation circuitry of the EtherVox (and I suspect also on the VCO's of the 91 series, but do not know this for sure). Even without ovening, the MiniMoog D had excellent stability (it used tempco and coupled transistors, but no controlled heating element).

My ideas about combining MIDI sequence and Theremin CV are more along the lines of having a note sequence whose register was changed, or having a sequence of some kind driving the VCF while tuning was controlled by the Theremin.. I never had any ideas about how one would use this ability really.. It just seemed to me that being able to mix MIDI and CV control signals in the Synth could be useful.. With CV, a one volt increase causes pitch to increase one octave - so a MIDI sequence being played should increase in pitch by one octave if the CV is increased by one volt.


Continued (?) Here (http://www.thereminworld.com/forum.asp?F=1&T=4812&cmd=p&p=1)
Fred