Mod For Moog Etherwave Theremin Adds Extended Bass Response

From Thierry Frenkel, theremingénieur, who developed the volume loop mod for the Moog Etherwave Pro used in many of Peter Pringle’s videos:

This is a demonstration of my most recent development – a small module which is soldered onto the Etherwave’s circuit board and which extends the pitch range of this theremin by somewhat more than 1.5 octaves towards lower frequencies.

The player will feel a much more stable and linear pitch field, even very far away from the pitch antenna. At the same time, the bass range of this instrument does not longer sound like a dying motorbike…

As the theremin goes very low, small computer speakers will perhaps not allow you to hear the extended bass in acceptable quality. Try using headphones or an external sound system…

Frenkel adds, “This recording of Rachmaninoff’s Vocalise Op. 34 has absolutely no musical value. I’m not a musician, I’m a theremingénieur.”

No additional information on the mod is available yet at Frenkel’s site, so I’ve contacted him to find out more.

If you’ve used this mod, leave a comment with your thoughts on it!

Via the Submit A Story page by Gordon Charlton

4 thoughts on “Mod For Moog Etherwave Theremin Adds Extended Bass Response

  1. You are right, there is no info on my website yet. This video was intended to be an appetizer, production and marketing will only start in summer. I decided this time to not to do "mass production" myself but to externalize that in order to have more free time for new developments… Wilco Botermans in the Netherlands will care about production and distribution (which will not prevent me from building and installing several modules myself for some very good friends…)

    The module itself will be installed vertically above the extension connector of the main circuit board. It will have extra solder pads for the wires which lead towards the Plus board (if installed). Two components will have to be partially unsoldered from the main circuit board and their pads connected also to the module with three short wires. A slight turn of L6 will be needed in order to re-center the pitch knob. Wilco will also provide a "factory upgrade" service for those who fear soldering.

    Randy George who spent the last few days in my home tested it and commented the pitch field: "Wow! How stable it is!"

    In order to answer the first FAQ which have reached me via several platforms:
    – No, the tone spacing will not be compressed in order to obtain the bigger range, but the pitch field will be larger. The player will have to step a little backwards in order to use the double-bass register.
    – No, the timbre of the "normal" pitch range will not be affected. The waveform and brightness controls will continue to work as usual.
    – Yes, at the end of the video, I'm playing in a very high register which goes also beyond the normal pitch range of the Etherwave. That has nothing to do with the new module, it's another story… It was only to show that the "ancient" pitch range remains unchanged.

    Stay tuned… more info to come soon. In the meantime you may use the contact form of my website for more detailed questions.

  2. Just wanted to say I thought your clip had musical value as well. It stirred emotion in me, which not all of these clips do.

  3. To add to the above, this module (ESPE01 -> Etherwave Standard Pitch Extension) is available via the website of A lot of thereminists have installed the module themselves, or had it done for them, and the responses have been very positive.

    Contradicting what is said above, the module does have some effect on the timbre of the Etherwave theremin. The sound gets a bit rounder and fuller, and timbre continues into the lowest range.

    Thereminist Thomas Grillo made an extensive comparison which can be viewed on youtube.

    Thomas Grillo is also one of four people who can assist with installing the module. The others are Gene Segal of Wavefront Technologies, located in Los Angeles, Thierry Frenkel in France and myself in the Netherlands.


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