Fixing Claravox volume antenna

MOOG's reply to John McEroe! I love it!

The Claravox output is a very hot line level signal, therefore it is important to implement your instrument into your setup correctly. Everything boils down to set up and gain staging. If you are using an amplifier, you run the risk of hearing volume bleed while sending a line level signal to an instrument level input. If you have the option to lower the gain on your amplifier, the amount of bleed would reduce. Monitoring the Claravox with a mixer between your amplifier or monitors allows you to adjust your settings on the mixer at lower volumes, and higher volumes on your sound source. Some latent signal can be present across all Claravox given the varying nature of how it can be implemented in ones setup, however it can be diminished if implemented correctly.

Best,

Z Briggs
Service Administrator
Moog Music

I would so much like to tell them that the issue is over, not thanks to them.
But the warranty would be over too.
Hope they don't read the forum, ha ha...

I could propose them a deal.
I tell them how we solved the issue and they do not void the warranty.
I think it's fair...

Would anyone like to buy mine? I've been meaning to list it on Ebay but have been too lazy.

Not me !

I just received the information from Alexander Klaus (aetherwellen-musik.de) who published a detailed description of the volume function, both in traditional and modern modes.
This is called "issue 22" on this page :http://aetherwellen-musik.de/Theremin-Instrumente-Instruments/Claravox-Centennial-CV-C-Theremin-Review-Improvement.

The modification I made is the shortening of R104 on the main board.
The resulting volume response curve is still too slow at low level but, at least, it solves the non mute issue.
Alexander is working on an improved version of the piggy-back module that plugs on the volume oscillator and detector board (issues 9 and 14).
It should solve the volume response curve issue in traditional mode.

I'll keep you informed.

The issues with Claravox continue to amaze me. Many of these problems seem incredibly bush-league and cold have been avoided through some basic acceptance testing and/or very low cost changes to some of the components used. That said, I have found it to be a very enjoyable instrument to play underneath it all. I do have concerns about the long-term viability of the instrument because so much of it is dependent on software which Moog (now InMusic) may not have much incentive to maintain.

Supposedly all the parameters can be controlled over midi, is that not true? So even if the software is no longer supported, you could still implement your own app to send MIDI over. It's similar with other Moog products, including their newer synths.

I have implemented the piggy back volume board CVC VREB V3 on my Claravox.
It works great !
It completely solves the non mute issue and the squeak noise issue and gives a much better volume response curve.

I had a very close and daily collaboration with Alexander Klaus.

No need to describe the module here. You can find the description on his site :
http://aetherwellen-musik.de/Theremin-Instrumente-Instruments/Claravox-Centennial-CV-C-Theremin-Review-Improvement
Scroll down to Issue 22.
There are two different board, V2 and V3.

Rather than using a prototyping board, I designed a specific printed circuit.
If anyone is interested, I can send the layout.

I now have a playable instrument !

Later, I intend to work on some of the other issues as described on Aetherwellen site.
Issues nr 11 is done. Next will come issues nr 5, 15, 17 and 18.