Hello all,

As I mentioned in a previous post, I had my semi-public debut last weekend at my synagogue retreat talent show.  I played "Over the Rainbow" to a jazz piano arrangement I recorded and edited.  This went O.K. overall.  I was pleased at how the accompaniment sounded -- someone told me afterward she thought it was a karaoke track I had downloaded.  I had trouble getting the pitch field set on the theremin -- although I'd let it warm up for more than 15 minutes, I could not get zero beat set properly -- the intervals were narrower than I was used to, and this made using vibrato pretty impossible.  The piece was very well received, I think because nobody had ever seen a theremin played live before, and there was just that "wow" factor of someone playing the air.  I was not satisfied w/the performance, but it was at least respectable, and nobody was injured.

The B3 is behaving normally now that I am home.  What could have caused this difficulty?

Hi there,

I hear your theremin screaming I need a better earth ground. Were you indoors using the amplifier you use at home.  I think the B3 gets it ground with a three prong plug on the amp?

Christopher

Beth,

At some point you may want to get yourself a Soundcloud account - assuming you don't already have one. Basic ones are free, you have to pay $50 or so a year to be able to upload new file versions on top of old and you get more space and more plays, etc.

But if you don't have one - the free one is fine to begin with. This will easily let you share your music with the world.

Rich

Hi Beth: 

I would be interested in getting your accompaniment to "Over the Rainbow" if you would be willing to share.

I find that my theremins (etherwave and melodia) sometimes behave differently when they are in an unfamiliar setting.  They seem to settle down after I play a bit. This may just be a case of nerves or perhaps physical objects nearby are effecting the linearity.  The suggestion Chris made above is worth looking into; the etherwave manual talks about the importance of proper grounding and I assume the Burns is similar.  Another possibility: the pitch adjustment on my etherwave is basically all the way to the left and one time when it was really cold I did not have enough adjustment until it warmed up a bit. I should probably adjust it but it normally works OK.

Hi there,

I hear your theremin screaming I need a better earth ground. Were you indoors using the amplifier you use at home.  I think the B3 gets it ground with a three prong plug on the amp?

Christopher

I was indoors, using the same setup as home, 3-prong ground.  I didn't really feel nervous, but maybe my brain wasn't working right in front of the audience.  The room temp was moderate.  What was happening was there was this really large field of silence for zero beat, which made me have to play close to the antenna w/small pitch field.  If I turned pitch too far leftward (counterclockwise), the intervals were way too wide.  It does not do this at home.

Now that I have some confidence that my accompaniment doesn't suck as bad as I thought, I will probably put it up on soundcloud.  But it does have a lot of individual rubato, so I don't know how useful others will find it.

Beth

Luna said: "What was happening was there was this really large field of silence for zero beat, which made me have to play close to the antenna w/small pitch field."

This is a very good clue, in my own theremin designs I have no Null point or Zero beat. My theremins go so low in pitch they just roll over to the other side. Some people might not like this but it makes for a happy theremin. It took me years to learn the secret to this until one day a moment of inspiration kicked me in the head. Today my forehead wears the boot prints of Fred, Thierry and dewster.

In layman terms the two pitch oscillators in your theremin are talking (coupling) too loud to one another. They should not know the other exists. My first guess: You might have had your theremin sitting on top of something while playing and not stand-alone on a mic stand? Then again was the humidity in the room noticeably different from that at home?

Christopher

Luna said: "What was happening was there was this really large field of silence for zero beat, which made me have to play close to the antenna w/small pitch field."

This is a very good clue, in my own theremin designs I have no Null point or Zero beat. My theremins go so low in pitch they just roll over to the other side. Some people might not like this but it makes for a happy theremin. It took me years to learn the secret to this until one day a moment of inspiration kicked me in the head. Today my forehead wears the boot prints of Fred, Thierry and dewster.

In layman terms the two pitch oscillators in your theremin are talking (coupling) too loud to one another. They should not know the other exists. My first guess: You might have had your theremin sitting on top of something while playing and not stand-alone on a mic stand? Then again was the humidity in the room noticeably different from that at home?

Christopher

It was on my mic stand, same amp, same cables, same power supply.  I didn't notice the room being particularly moist or dry.  It was just...different.  Frustrating.

It was a beautiful day but the air was probably cold and dry?

Earth ground is still high up on the list. I think any Pro Thereminist would want to own a meter that would measure the quality of the wall sockets they are plugging into, this is beyond the scope of the average person.

A less effective but an improvement might be to wear a wrist strap so you are grounded to your instrument. This strap at Amazon may have too much resistance to be effective. You could make your own using a metal dog choke chain around your ankle and a 3' wire with alligator clips on both ends to connect up to the Y adapter, it might look fashionable, others might chime in on this. ruff ruff

This will move the pitch response back out towards you for sure. Dan the man who designed your theremin could give you better clarity on where to connect the alligator clip on the strap. I myself might use a Y adapter at the theremin output jack. Run the amp from one side of the Y and on the other lead use a razor blade to shave off a bit of the insulation so the alligator clip can have direct contact to the braided metal mesh.

This also helps avoid zapping your theremin from static discharge. !#$%

Christopher

Edit: Amazon let me know static wrist straps have a 1 meg resistance, this could "never" work as the needed substitute ground loop when connecting to a theremin. Go with the homemade approach, the dog choke chain collar on the ankle is a good idea or connect to a metallic object against your flesh inside your belt line. Use an alligator lead with clips on both ends. You could trim a little rubber insulation off your existing amplifier cord.

I recently had the same problem taking an Etherwave Standard to a friend's house to play to his piano accompaniment.   It worked fine in my home but I could not get the pitch field tuned wide enough to play properly in his music room.  I could only figure that it was the different amplifier being used or perhaps some other anomaly in his house or electrical system.  

I then remembered a video of Leon Theremin having the same problem in "Theremin:An Eletronic Odyssey" with his own theremin that he built decades before.   I believe he was placing a pair of pliers of some other tool next to the pitch antenna to extend the field.   

Remembering this I went to my friend's kitchen and got a piece of aluminium foil and made a small ball of it around the top of the antenna and it worked!   I am not saying this would have worked for you but it may be worth experimenting with at some point in case you ever encounter the problem again.

I feel a little better hearing this has happened to others, including Leon T. himself!  I'll explore the "dog leash" approach, also the aluminum foil (which sounds easier).  I wonder if this will clean up the sometimes fuzzy sound I sometimes get at home, too.

Christopher, it was a relatively cool, dry day.