ModularGrid Rack

I would appreciate a few hints or an full on roast concerning the rack from the link.
Could this possibly work as a double voice something something theremin?
Thanks


No, it would be a single voice...you've got one aerial for pitch (closer = higher) and the other for level (closer = quieter, with touching this aerial acting as a "mute"). Or at least, that's how it SHOULD be. I worked for years with a Maestro unit (one of Tom Oberheim's designs...NOT Bob Moog, since that unit came out in the pre-Norlin period) that had an amplitude implementation which worked "backwards": get closer, it gets LOUDER, and "muting" wasn't possible at all. Finally sold it for a pile of money, got a Moog Theremini instead which offers more connectivity, a far better sound module, etc.

My concern here is that the case might not be wide enough. Those aerials need some distance so that you're not accidentally changing pitch when you need volume changes, and vice-versa. A 1 x 84 would probably work better here...sort of like...wait for it...
ModularGrid Rack
OK, there we GO...width is now 84 hp, which keeps the aerials further apart AND which allows for some trickery.

You'll notice that this seems to violate one of my own rules, namely that mults don't belong in small builds. However, given that this ISN'T a "proper" synth and that this really NEEDS them to distribute various signals in parallel, there's three (technically, four) of them to help with that. Two are at the obvious places, to distribute the various aerial signals. The others make sense when you look at the signal flow...

SO, after the amplitude (left) aerial and its mults, you've got a pair of ADSR envelopes which get gated via the left aerial. Then there's one of Noise Reap's weird dual LFOs which has some capabilities for scrambling its OWN operation for weird, non-symmetrical modulation curve outputs. After that is a Bragi ASK, which provides two attenuverters with 3-way multed outs for altering modulation signals and distributing them to various destinations.

For the oscillator, I opted for a Twin Waves mkii, which gives you two oscillators, several useful internal routings, and a quantizer which allows you to play discrete steps in addition to the typical theremin glissandi. Another mult after that lets you distribute the oscillator outs to the various audio processing modules that are placed just after it. Mind you, you don't HAVE to use the mult there; it's just as valid to patch those in a post-VCA configuration...especially given the VCAs in question. I went with one of Plankton's dual VCAs that use a NuTube triode which you can slam the crap out of for some distortion/waveshaping.

And since we're definitely now in stereo, the VCF I chose was Bastl's Ikarie, a very odd and somewhat nasty stereo filter that can behave...or get really gritty, plus it has a dual-peak architecture so that you can have some similarly-tracking but different-sounding filter responses in its two channels. Then, effects...theremins are awesome with some processing, so I opted for Happy Nerding's excellent FX Aid XL for a useful effects "library". Then past that, I put in a HN 4x Stereo Mix...this lets you deal with the stereo outs of the VCO, VCA, VCF, FX Aid...however you want to deal with them in parallel so that you can have sound events that involve the sound "evolving" between those modules via some judicious patching of the various modulation bits. Lastly, the HN Isolator is a MUST here, since you're dealing with RF circuits and you don't want crud getting into those and destabilizing them...which is an inherent issue with theremins, and why many of the cheap ones sound like total ass. Then mult, pitch aerial, and there you go!

As for aerial placement, that'll vary a lot depending on how you feel comfortable with interfacing with the aerials. In theory, you can keep the amplitude aerial partly un-telescoped and aimed sideways so that you've got something with some similar ergonomics to the RCA and Moog designs. Pitch aerial definitely goes straight-up and at full extension, though. And remember to keep this away from metal surfaces which will couple with the RF controllers and cause various control annoyances.


Wow Lugia, thank you!
I'm looking up some of the modules suggested; So many mults! Trying to wrap my head around patching... Is swapping one of the the 4x4 mults for another ASK a reasonable consideration?
As for the case, would an alm / brute case do?


Wow Lugia, thank you!
I'm looking up some of the modules suggested; So many mults! Trying to wrap my head around patching... Is swapping one of the the 4x4 mults for another ASK a reasonable consideration?
As for the case, would an alm / brute case do?
-- krmk

You could do that swap, but you'll have to resort to some inline mults to get certain routings to work. As for the 'Brute case, yeah, that should work even better since they're wood...helps avoid signal leakage between the aerials and therefore playing issues that might pop up due to them. Also, you can then add the ASK and keep the mult, since these run 88 (or 89, depending on who you ask) hp.


Thanks Lugia,
from what I understand the rackbrute cases are aluminum with a bit of wood on the sides (amazing vintage optics?).
After some consideration my mind wandered off from moar modules, to... playing.
Twisting knobs and playing theremin won't go together very... um... melodically, right?
Is an expression pedal module worth consideration?
I would rather not look too much into guitar pedals as an fx alternative (researching modular is enough).
Do you use your theremini as an cv source?


After some consideration my mind wandered off from moar modules, to... playing.
Twisting knobs and playing theremin won't go together very... um... melodically, right?

Yes and no. It's true that the OG theremins had minimal timbral control. But in the present day, you've got Peter Blasser making his post-West Coast devices which sometimes house multiple theremin circuits, with the ability to mess with those to use them for all sorts of purposes. The Deerhorn Organ (https://ciat-lonbarde.net/ciat-lonbarde/deerhorn/index.html) actually has three different theremin controllers, with the ability to patch them into all sorts of configurations.

Is an expression pedal module worth consideration?

Can be, sure. But you can just as easily use a passive expression pedal between patchpoints with no need for an external pedal module, or an active one as long as it outputs a 0V to +5V voltage range. I like some of the smaller pedals coming out of China these days, such as https://www.amazon.com/Sonicake-Vexpress-Passive-Expression-Effects/dp/B077PVVC38/ref=sr_1_14?crid=2UEUU3PEQ1ANY&keywords=expression+pedal&qid=1662014966&sprefix=expression+pedal%2Caps%2C92&sr=8-14 They're sturdy, small, and inexpensive so that if you wanted to use a few of them, all you'd need is the long 3.5mm to 1/4" cables to go to and from the modules. I have a few of those Sonicakes, btw...got one some time back, and it was a real "convincer".

I would rather not look too much into guitar pedals as an fx alternative (researching modular is enough).

Oh, yeah...I've got a good "library" of them, and thanks to Ryan over at 60 Cycle Hum on YT making his jaw-dropping clip about the Cuvave fuzz , I got deep into the Chinese stompboxes. And the "why" there gets explained by that YT clip...these Chinese pedals are really more like little boxes of sonic surprises. Yes, a huge number of them are supposed to be clones of existing models from other manufacturers, but note that "supposed to be" part. Given differences in component tolerance, the reverse engineering processes they use, and on and on...they never exactly behave like their counterparts. So when, for example, I hooked up a Joyo "Classic Flanger" and expected basic plain-jane flanging but instead got something like MXR's wall-powered tripout-monster (not in production these days) from the 1970s...yeah, that's why I get these things. Just check all of the YT demos by bunches of YT creators and see how things sound in various hands, and you'll see what I'm talking about here.

One I will suggest, though, is Aural Dream's "Breath Delay". Basic analog delay...except for this one little switch marked "NO" and "GH". And what THAT does is to let you build up layers of stuff on the delay tails when it's set to "GH" (for "GHost", with "NO" for "NOrmal" operation). It's a little bit like Clouds, minus the ability to directly manipulate what's in its signal path like the synth module. Unlike Clouds, though, the pedal costs less than $30.

Do you use your theremini as an cv source?
-- krmk

Oh, yeah...and that can get fun when I start messing with the CV once it's out of the Theremini. Using one to "control" a Wavetek function generator is simply NUTS due to the different CV standards, for example, but it can do things that you can't get to with just the knobs on that device.