Theremin B3 150 dollar box BAD Harmonic wolf tones

If the wall-wart that came with your theremin uses a switching power supply, you may get some better results if you find an older wall-wart with a linear supply.  I know that one of my theremins has a real problem with the noise coming out of a switching power supply.

I suspect you know how to identify them, but in any case the linear wall-warts are usually bigger and heavier and have a lower current capacity.  If you do try one just make sure that it's output is regulated to the stated voltage; many are not and can have a much higher no-load voltage than the rated voltage on the label.  Also make sure that the polarity is correct.  Some are reversed.

But it sounds like you are on the RC battery path, which is the ultimate noise-free choice.  Of course you will still need that ground wire, and it pays to make sure that the ground that you connect to doesn't have noise loads such as motors or switching power supplies.

Good luck and have fun!

I guess that the dc battery will not solve the catching of hum via your body and the environment. Try it out by touching the mass of the output cable with one hand and playing with the other hand. The pitch high then takes a jump but the sound should be really clear and the hum sideband modulation will be significantly reduced or vanished. But how to ground the body if we need the second hand for the volume control? You could plug a crocodile clip on your big toe...

I do not know if the Moog EW is here better in your heavy contaminated environment. Do other forum users have a similar phenomenon using their theremins?

If the wall-wart that came with your theremin uses a switching power supply, you may get some better results if you find an older wall-wart with a linear supply.  I know that one of my theremins has a real problem with the noise coming out of a switching power supply.I suspect you know how to identify them, but in any case the linear wall-warts are usually bigger and heavier and have a lower current capacity.  If you do try one just make sure that it's output is regulated to the stated voltage; many are not and can have a much higher no-load voltage than the rated voltage on the label.  Also make sure that the polarity is correct.  Some are reversed.But it sounds like you are on the RC battery path, which is the ultimate noise-free choice.  Of course you will still need that ground wire, and it pays to make sure that the ground that you connect to doesn't have noise loads such as motors or switching power supplies.Good luck and have fun!

Another thing overlooked, my ground is plugged into a strip that has other warts...:-(

I guess that the dc battery will not solve the catching of hum via your body and the environment. Try it out by touching the mass of the output cable with one hand and playing with the other hand. The pitch high then takes a jump but the sound should be really clear and the hum sideband modulation will be significantly reduced or vanished. But how to ground the body if we need the second hand for the volume control? You could plug a crocodile clip on your big toe... I do not know if the Moog EW is here better in your heavy contaminated environment. Do other forum users have a similar phenomenon using their theremins?

I may try an ankle strap similar to the ones that are used on my computer tech bench, but will remove the 1000 ohm resistor. At this point with the new monitor speakers I am more then satisfied with the tone, Time to start prcticing.

Looks like my thoughts on a battery for pure voltage power supply is not new, this guy drives his theremins with a 9 volt battery, have a look.  2 min/55secs in .

Playing a theremin off of battery power is easy; if you want something really plug and play get something like this: https://www.amazon.com/Portable-Power-Station-155Wh-Generator/dp/B07MLHFT4B (that's what I use). The thing you really have to deal with is how to ground; there are a few ways to handle this but as you will know by now you can't get a good sound without a good quality grounding

SClancy, that's a fantastic video of Arthur Harrison, thanks!

I commented on this youtube video recently. It would be nice if i could copy and paste it over here, but i can’t, so i’ll try to rephrase. 

I’ve read every forum discussion about grounding I could find, and honestly most of it goes over my head or exceeds my abilities (I do not feel confident in opening my B3 up and altering it and standing on or tucking the cords into my sock hasn’t made much difference in timbre).

I just moved into a friends house with a designated “music room”. I found the “sweetest spot” in the room where the B3 sounds least like a race car...but it’s still pretty bad/fuzzy. The room is in the basement, water pipes and heating ducts run through it (theremin is as far away from these and metallic instruments/objects as possible) and there is only one outlet in the room with a power strip where theremin, amps and potentially a keyboard or synth would all be plugged in. Obviously not ideal, but it’s what i’ve got.

About a month ago i brought my theremin and amp over to a friends to jam in her basement music room with almost identical conditions (one outlet, pipes etc) and found a very particular tiny spot near the exposed heating duct where the lower tones of the theremin sounded more clear than ever before. It was wonderful. I scooted all around my basement room and couldn’t reproduce that experience.

 The youtube video OP posted gave me hope that even in an unideal environment it is possible to get decent sound, but without the know-how he has I’m not sure what I can do. It seems like i should be able to strategically place a conductive object to alter the field, and I will experiment with that but I thought I should reach out before going in somewhat blind..and I don’t want my account to be deleted for being inactive on the forum.

Connect the negative side of your theremin to here.

not positive this is in response to me, but if so-the B3 is only two pronged. it’s plugged into a 3 prong extension chord right now, it sounds only very slightly less like an engine than when it was plugged directly into the wall. I’ve emailed burns support but nothing yet:

It is safer to use an amplifier using a three prong plug. Ground would come through your audio cable.Did you post a sound sample so we get a better idea of the issue?Christopher

 It is plugged into an amp with a three prong plug, I’ll record it today and post it later tonight. it sounds very much like the the youtube video included by the original poster on this thread. I appreciate your help.