Theremin discussion

The Open theremin is pretty good. I actually use mine quite a lot in my home studio, since it can be tweaked easily to match my cramped space.
My main performance theremin is a PAiA Theremax…that was also my first one. I really love it, as it has a slightly buzzy tone, sort of a sharkfin waveform (a bit truncated on the lower on the scope)
I also have a tube theremin and an FPGA theremin that I’m always tinkering with. Last but not least I have a Model 142 that I found as a boxed, assembled kit on ebay.

I’ve played Etherwaves and thereminis before. I’m not a fan of the theremini…it’s not the plastic, it’s the tone…having said that the Etherwave pro is a wonderful instrument, but simply not worth $6k+ to me…even though I agree it’s a lovely looking instrument.

I quite like the look of the Claravox, and it seems to be an improved implementation of both the Etherwave Pro and the Theremini in one box. I’m concerned that the fabric faces will get damaged, but I like the portability, and worrying about cloth is probably without merit, as I have a few ancient amps with cloth faces that are still beautiful!

Yes, I preordered one.

Of course, I’d rather have a Tvox Tour…or even a Subscope. But I think the Claravox will be a great addition to my quiver, and I think it will sound as good as my Klippinger-based tube beast (which weighs 88 lbs in its enclosure). It’s hard to tell how it will actually sound based on a youtube clip.

If you can afford the $$ to buy one, and you are theremin-curious, I think it’s a reasonable investment. Moog has already announced that after the pre-order period they will not be for sale any more.

But they are like any other instrument…they take time and practice to master. I played 10 to 12 hours a week for 4 years before I started to sound like anything other than a kid on a slide-whistle. If nothing else, it really teaches you how to be still

The real value in a great theremin is really about pitch linearity. Not a big deal on volume, and I actually prefer a more log-shaped curve on the volume. But a long, linear pitch draw is what makes an instrument playable…and that is what is amazing about the EPro. I’m hoping the Claravox is similar! And it’s what is amazing about the FPGA based theremins.

But that’s where the Open theremin and most other digital or Arduino based instruments fall down…not tone, playability. The Theremax is a good middle ground.

But if you aren’t a theremin player, you couldn’t know that.

There are a lot of other monosynths that cost far more than $1500, and not too many people would want to argue that they have no value compared to your [insert DIY Arduino monosynth of choice here]

And I have to admit…I use and play my Otamatone Techno a LOT!!


Speaking of which:

Sounds pretty good too.


Speaking of theremins,
i’ve been trying to come up with a circuit for an Ondes Mardenot sine wave oscilator
and it turns out it is a beat frequency oscilator like a theremin.

Does anyone have schematics for an oscilator like that?
i managed to get close in a simulation but it still isn’t right.


How close to a real Ondes Martenot are you trying to get? People have hooked up an Ondes-style controller to a modern VCO. Apparently you can even buy a controller commercially, if you have $3000 to spend.

On the other end, if you want to replicate an original Ondes, maybe you can get some ideas from this blog.

In between it seems to me you could take an existing modern Theremin circuit and just change the control source to an Ondes style controller. I guess Open Theremin under the hood is really a digital signal generator with a Theremin style controller, so that might not be what you want to copy, but there’s a bunch of other Theremin schematics here.


Yes, it’s a wave table oscillator attached to some circuitry that handles the antenna signals.

I looked at the Ondes Martenot a few months ago. That’s a very weird instrument. A bag of mysterious powders? A fake keyboard?

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yeah, i want it to stay analog.
and i ended up reading through that article already.

this is the circuit that i’ve put together so far

it’s two hartley oscilators and a heterodyne receiver i found online
the oscilators kinda work although they’re distorting a bit
the receiver doesn’t seem to be working…

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Australian journal Silicon Chip has come up with a bunch of Theremins and … ARRRRRRRGH!!! … I have the most complicated lying around. Just have to fix the equalizating coil and get it howling.
Articles can be downloaded (for a fee) and PCBs and/or kits may be available from Silicon Chip or Jaycar.

I went for this one

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I was always fascinated by theremins.
But I’m looking for is an antenne with CV out.
The only info I found on the forums is to use the volume part of the Bigbriar Etherwave.

So I took the PDF and put everything in Kicad.
Here you can take a look at it:

I’m not sure what my next step will be :smiley: there are a lot of “random” value resistors and capacitors I don’t have, inductors and in general, reading the PDF, it sounds like it’s a very fragile circuit.

The “Volume Control Voltage Output Circuit” comes from the Hot-Rodding chapter of the PDF

Edit: the resistors and capacitors are not that random in the end, I have most of them.
The issue is the variable inductor


Just spotted this coming soon. Quite interesting.


From episode 4 of Loki.

Judge Renslayer has an Akai open reel deck in her office, and she’s playing Rockmore’s recording of The Swan.


That’s nothing, in episode 1 Loki’s booked into the TVA by an agent who’s got his Korg Volca Keys hooked up to an unseen MIDI keyboard!


Not sure I’d want to be the person at Korg whose design for one of their current cutting edge products was selected to fit in with the whole TVA archaic vintage technology vibe…


I want a Deerhorn… its ciat-lonbardes take on the Theramin.


Always more things to build.


(No voice actually, just theremin)




Bah, who needs to spend $900 on an Etherwave?


274 Japanese people playing Beethoven on theremins hidden within matryoshka dolls.

As one does.


My new OpenTheremin. I printed a (red!) case for it.