Fixing Claravox volume antenna

Posted: 9/8/2023 7:15:48 PM

From: 30 km south of Paris (France)

Joined: 12/23/2022


Hi Andre,

Suffice to say, the Claravox is going to behave differently from the average Theremin. You are correct that normally there would be no sound present when placing a hand near the volume antenna. Due to the specific design of the Claravox, some latent signal can come through when using Traditional Mode. This behavior is unrelated to the issue alluded to on early models.

There are some ways to mitigate the presence of the latent signal, however there is no one way to eliminate it completely, so there is a chance it will be heard depending on several factors. The first thing we recommend is to perform the calibrations listed in the back of the manual starting on page 63. After performing said calibrations, we then recommend following the instructions on page 20 under "Tuning the Volume Antenna." The last portion of that instruction is important for mitigating the latent signal.

If the latent signal is still coming through, you can make some manual adjustments via the trimmer in the small hole located below the volume antenna. You will need to go slow and make very small adjustments by ear until the signal is reduced with your hand near the antenna. Note that by making the adjustments, you may need to alter the panel settings to dial in the desired volume control. It might take some back and forth to get it just right.


Z Briggs
Service Administrator
Moog Music

To me, a simple summery of this answer is :

"Hey, a theremin is supposed to make music. Why do you want to silence it ?"

I could answer with the famous sentence : the silence after Mozart is still Mozart. But how can I play the silence after Mozart ?

Now, imagine I have a problem with my car. Even if I stand on the brake, I can't stop it. It continues to run very slowly.

MOOG MOTOR answer :

"Suffice to say, this car is going to behave differently from the average car. You are correct that normally it should stop completely when you press the brake pedal. Due to the specific design of this car, some latent speed may remain when driving in Traditional Mode.

I suggest that you park your car on a large enough and flat area and carefully adjust the steering wheel so that it will continuously run in circles. By adjusting the trimmer behind the little hole on the dashboard, you should be able to reduce the speed enough to allow you to safely leave the car.

Best !"

As we say in french : "Circulez, y'a rien à voir" !

Posted: 9/8/2023 9:16:48 PM

From: Northern NJ, USA

Joined: 2/17/2012

"I don't know if 3 is better, worse than or equal to 2."  - André

I would give 2 a shot, it gets the wire away from the coil drive end and effectively shortens it by wrapping it all around the end of the antenna socket.

Sorry about your non-answer answer from Moog.  There must be a fix, and I wonder how involved it might actually be?

Posted: 9/9/2023 6:08:53 AM

From: 30 km south of Paris (France)

Joined: 12/23/2022

A "2+" version could be to shorten the green wire to make a straight direct connection.
I'm going to try that by replacing the wire.
If I have to return the Claravox to Moog for warranty, I'll put the original wire back.

I agree, there must be a fit.
Here is my answer to Moog :


Oh my God, I was expecting any answer but this one !
As John McEnroe said in 1981 : "You cannot be serious !"

This theremin is supposed to be the best, or at least, one of the best theremins in the world.
Also, it is one of the most expensive.
And you are telling me that, unlike my Etherwave, 4 times less expensive, unlike any other theremin in the world, I cannot silence it completely ?
No, you really cannot be serious.

When I play a song and at the end, the accompaniment, in a long decrescendo, goes down to a pure silence, my theremin is still playing, the audience can hear it, and I cannot stop it ?
What can I do ?
My right hand is keeping the pitch.
My left hand is trying to silence that note as much as possible.
Am I supposed to flip the mute switch with my teeth ?
No, you really cannot be serious.

Even before receiving your answer, I did perform all the settings you recommend, including the trimmer adjustment with the famous Moog red tool.
It has very little effect on the minimum sound level.
At the setting that gives a minimum sound, it is still too loud and the volume response becomes quite strange, even if I try to adjust the front panel knobs.

I know at least one person whose Claravox can be completely muted in traditional mode.
So there is a way.
Please… please find it for me.

Best regards


Posted: 9/9/2023 7:08:09 AM

From: Portland, Oregon

Joined: 2/22/2018

Very generational reference to John McEnroe there Andre

Posted: 9/9/2023 7:42:37 AM

From: 30 km south of Paris (France)

Joined: 12/23/2022

Yes, may be the guy at Moog wasn't born in 1981 !

I made the green wire yellow and shorter.
I don't notice any difference and still can't mute the damned thing.

Posted: 9/9/2023 11:19:59 AM

From: Northern NJ, USA

Joined: 2/17/2012

"I made the green wire yellow and shorter.  I don't notice any difference and still can't mute the damned thing."  - André

Well, you can't say you didn't give it the old college try!  The Aetherwellen site is certainly dotting every I and crossing every T when it comes to ruling things out & fixing stuff.

I'd be hopping mad if I were in your shoes, and I think it's good that you're taking them to task for their rather insulting reply - perhaps it will motivate them to find some grease for the squeaky wheels.

Posted: 9/9/2023 12:12:30 PM

From: 30 km south of Paris (France)

Joined: 12/23/2022

Yes, they did a very good job on Aetherwellen site but they don't talk of the "no mute" issue, which is surprising.
This probably confirms that there are Claravox(es) that do not have this issue.

I'm going ask them if they have heard of it.

Edit : mail sent to Aetherwellen.
Edit 2 : I misread the Aetherwellen site. They actually do address this issue.

Posted: 9/9/2023 7:54:03 PM

From: 30 km south of Paris (France)

Joined: 12/23/2022

A few tests this evening.

I noticed that when I try to adjust Brightness, Wave, Filter or any other potentiometer, there is a scratching noise, as if the pots were defective or low quality.
In fact, the pots are not to blame.
If I turn them very carefully in order not to move the theremin at all, there is no noise.
If I slightly shake the theremin case, funny noises appear. In fact, there are big steps of volume changes.

Although the part of the antenna that makes contact has been sanded by Moog, the contact is of poor quality.
Insufficient spring contact, may be (see issue nr 16 on Aetherwellen site.)

I made a Video of what happens.

Bonne nuit. Demain est un autre jour.

Posted: 9/10/2023 12:21:33 AM

From: Northern NJ, USA

Joined: 2/17/2012

"Insufficient spring contact, may be (see issue nr 16 on Aetherwellen site.)"  -- André

It's not too surprising.  The antenna contacts are apparently one of the weakest links in the Cvox.

Posted: 9/10/2023 5:22:30 AM

From: 30 km south of Paris (France)

Joined: 12/23/2022

Moog will probably say that I'm not supposed to touch it while playing.
But those volume step sometimes occur during playing !

The plumbing system of the Etherwave is a simple and safe solution.

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