Thoughts wanted: The first Theremin

BTW: Does anybody know the German company "GOLEM-instruments"? They claim to make theremins since 2006, but I can't find any "objective" review on their products.

Not that I don't like moog, but if there is a local manufacturer - why not support them if the quality is decent ....

OK,

answer on my own question: Thierry had already his hands on them: They are CRAP.

OK,

my (for now) (maybe) last question: Anything againts buying the Etherwave as a kit - or is an assembled device prefereble because it is calibrated "as one" or something like this?

The needed work to assemble the kit is no concern to me.

You might take the kit. It's just very, very important to paint or varnish the cabinet with a paint or lacquer containing NO metallic parts before assembling.

I recently had to "fix" such a kit-built Etherwave which was left in the raw wooden housing. It had worked very well last summer, but when the winter came, the pitch range got more and more limited. I found (after searching some time around because I had never seen this phenomenon before) that the raw wood had absorbed so much humidity that it represented such a big additional capacitive load to the antennas that it could not longer be compensated by internal re-tuning the oscillators...

After having spent 3 days and nights above an electric heater (Thank you, French government, for cheap nuclear power ;) ), everything was basically working again and after waiting a few more days for the wood to really dry, I applied a layer of protective transparent shellac based varnish, so that in the future, the wood would not longer absorb such high quantities of humidity.

"I found (after searching some time around because I had never seen this phenomenon before) that the raw wood had absorbed so much humidity that it represented such a big additional capacitive load to the antennas that it could not longer be compensated by internal re-tuning the oscillators..."  - Thierry

Yeah, wood isn't the best material for Theremin cabinetry because it weakly interacts with the capacitive field.  Plastic is better.

I have found that precise tuning of the Moog MIDI Ethervox theremin is not always possible.

Unlike the Etherwave, the Vox does not have any internal, adjustable pots, so you have to depend entirely on the main tuning knob to set the configuration. I don’t know exactly what is responsible for the variation in “tunability” - it could be that temperature and humidity have something to do with it. I like my zero beat spot to be about 20 inches from the pitch antenna but sometimes that is just not possible.

When this happens, I just switch the antenna that came with the instrument for an RCA antenna and the problem is solved. The original Vox antenna (similar to an E’Wave antenna) is hollow, lighter and thinner than the solid, heavy, nickel plated brass antenna of the RCA, but the RCA antenna is tapered at the base so it fits perfectly into the E’Vox receptacle.

"When this happens, I just switch the antenna that came with the instrument for an RCA antenna and the problem is solved."  - coalport

What's happening is the two antennas have different intrinsic capacitances.  Intrinsic C is mostly governed by exposed surface area, and not geometry so much.  So solid or hollow won't really matter.  You might make a simple two section antenna that telescopes enough to cover all tuning scenarios.