Theremini "pitch stability" issue?

Hi all, I recently purchased a Theremini and have been having loads of fun playing around with it. I've encountered an issue with it, though, and was wondering if anyone else has experienced the same.

I'll preface by noting that I am by no means a "serious" thereminist--I bought the Theremini to have a little fun playing melodies and to challenge myself with a unique instrument. The videos I've seen of skilled players have been very inspiring, and I look forward to improving my own ability.

Unfortunately, I'm a little disheartened at this early stage by what appears to be an issue with pitch stability. If that's an actual term of art then I'm probably misusing it--what I mean is that in certain positions, the pitch "jumps" one note away from the pitch I'm attempting to play. This is with the Theremini's scale set to "Ionian."

For a little while, I was able to convince myself that this was simply due to my novice inability to hold my hand steady enough, but as I've been practicing fingering techniques in playing the scales I've noticed that while I do just fine with most of a scale, there's always ONE stubborn spot in an octave where things go wrong. E.g., when I try to hold an E, the pitch plays an E, then jumps to a D, then back to E, then down to D, and so on. The jump isn't "smooth," either, as you'd expect if it were the result of an unsteady hand--there's a distinct skip from one note to the next with no intervening pitch (this is, obviously, with the pitch correction turned completely off). Additionally, a pitch near this trouble area may "stick"--that is, it will play a pitch without modulation even if I move my hand slightly in either direction.

The Moog Theremini manual has a "FAQ" which includes the topic "My Theremini seems very unstable." They instruct you to make sure you're using the power adapter that came with the Theremini (I am), to make sure you're plugged into a grounded outlet (I am), and to unplug any powerline network adapters (I've none). Additionally, I ensured there were no large metal objects near either antenna.

So has anyone else experienced this with the Theremini? I'm eager to hear what others think may be the issue.

Hi Ynote

 

I have a Theremini too, and one day in the place that i work, i played my Theremini and the tunning was horrible, there wasn't time with a tunning stable, the tuner of the screen always it was moved around of the center of the note. In my place's work ain't got earth-ground connection, something very dangerous, so any Theremin that i've used there has had some problem for bad electric connection. 

Try to do this, touch with your finger the "ground-screw" at the back of the Theremini, the tunning stability must become good if you stand very quiet with your Theremin, if it doesn't result, so there is other problem.

 

good luck

I have the same problem. I triyed with my finger touching the "ground screw" and it works! !! But theremin must be played with botth hands!! How can I do that? Any sugestion.

Sorry for my terrible English,  I'm not an English speaker....

 

Just run a wire from this screw to your body (your hand or foot). This way you ground yourself to the theremin.

Not sure about this new device, but for regular theremins all you have to do is take the output cable and tuck a little loop of the wire inside your sock, or take off your shoe and stand on the wire.

Don't do this outside during thunderstorms.

The more of the instrument cable that is on the ground, the better, use a long cable.

Also, turn off the auto pitch correct and then the pitch will not jump to the next available note.

As for the player, the best grounding is sitting upon the earth. Unless you have very large feet. Like mine.

This pitch instability seems to be common issue for Theremini owners, as I've seen not only on this forum, but elsewhere as well.

I'm happy to say that after a couple of weeks of my own struggle with it, and almost sending my Theremini back to Moog for repair or refund, I've resolved the issue.

The resolution was to use a 12v lithium battery pack - the kind you can find on Amazon for around $20 - $30.

I unplugged the stock 12v wall-wart that shipped with the Theremini, and instead plugged in the battery, and now find the pitch stability to be much improved.

I had a similar issue with the Theremini - I even sent it back to the shop for replacement which they did

After the new one did the same thing I realised it was probably something I was causing. It turned out to be a laptop I was running at the time. As soon as I unplugged that laptop from the same power supply as the Theremini the notes became completely stable.

This pitch instability seems to be common issue for Theremini owners, as I've seen not only on this forum, but elsewhere as well.I'm happy to say that after a couple of weeks of my own struggle with it, and almost sending my Theremini back to Moog for repair or refund, I've resolved the issue.The resolution was to use a 12v lithium battery pack - the kind you can find on Amazon for around $20 - $30.I unplugged the stock 12v wall-wart that shipped with the Theremini, and instead plugged in the battery, and now find the pitch stability to be much improved.

Can you point me towards the kind of battery pack you bought please?  I'm having a similar issue, and I'd like to see if it resolves it.

Every time I cook a chicken breast I think of the Theremini!

Even setting the pitch correction knob to its "off" position will remain ineffective for all but nine of the presets. These nine presets are the only ones that allow to to override quantization. They are Presets:

01 CLASSIC THRMN
02 SUPERFAT SAW
06 RIBBONS
07 CHARLIE MUTE
09 FLUTTERFLY
18 LONG ECHOES
22 FROLICKING
25 LOST IN FOG
29 OMICRONPRESET

Turn the pitch correction knob all the way counterclockwise and you're good to go.