possible technique for consistent interval spacing

so take this all with a grain of salt since i am still a novice, but it seems to me that it could be possible to achieve consistent tuning by setting two reference points on the top front edge of the theremin housing and always tune so that you get the same pitch interval between the two points. so for example on my etherwave standard i seem to get a decent wide range adjusting so that when i place my finger on the front right edge (http://www.flickr.com/photos/35634876@N08/3293181746/) and the point right above the start of the control panel (http://www.flickr.com/photos/35634876@N08/3293181734/) the pitch changes by an octave. if i need longer note spacing or need to play higher, i set the tuning so that placing my finger on the two points gives me a pitch change of a fifth... i am hoping that this will keep note spacing consistent to help foster muscle memory.

shrug. could work, right...?

You will see that the note spacing will still vary in function of the distance between your body and the theremin, especially in the lower register, even if you seem to have the same spacing at your "checkpoints".

Things are not as simple as you think...

argh! I suspected there was a reason no one else used such "checkpoints"...

anyhow, thanks again for setting me in the right direction, thierry!

I think "checkpoints" could be somewhat helpful, used along with other such measurements (distance of stance, etc.). This would also help train your muscle memory to be able to "adapt" itself to the slight differences in tuning each time.

In fact, one could argue that exact tuning is nearly (if not completely) impossible. To achieve more consistently EXACT tuning, one would need to maintain a strictly regulated diet, install advanced climate control where the theremin wil be, never move the theremin or anything else around it, and wear the same clothes when playing. Even then, the electronic components would need to be somehow monitored for accuracy. This is simply not feasable.

Instead, I'd say base tune to the checkpoints and then fine tune to what feels right as you play. When you get to a point during your session where it feels right, carefully (without moving stance) recheck your checkpoints to see where they lie now. Also, measure the distance between your closest body part to the closest point of the theremin, and note stance. Next practice session (after warmup), base tune to the new checkpoints (and stance measurements) and fine tune throughout. Repeat process until natural instinct takes over.

Adaptation is a key skill in theremin playing. :)

~Dan

Interesting topic! These are my personal thoughts ...

Actually, it's something I've given a fair amount of consideration to over the last year. When I first started to play, the same thought passed through my mind as yours, and I tried a few experiments.

When learning to play the theremin I soon came to the conclusion that tuning as consistently as possible was absolutely vital if you wanted to establish reasonably consistent aerial-fingering that the "muscle-memory" wouldn't forget! But I also soon realised that absolute consistency in tuning is virtually impossible.

One problem with you marking the theremin case with two reference points that, when your fingers are on them, give notes a fifth apart ... is that you don't play the theremin on its case. The same two fingers held the exact same distance apart at your regular playing height almost certainly won't be a fifth apart because the note field curves and notes are closer together nearer the top and bottom of the pitch field.

You can test this by holding your right hand about four inches from the bottom of the pitch antenna and moving it slowly upwards keeping exactly parallel with the antenna; the note will change a semitone or two or three between the top and bottom.
Another experiment is to start with your right hand at the bottom of the pitch antenna and move it slowly upwards while trying to stay on the exact same note. You'll find you have to gradually move your hand further away from the antenna. Go right up above the antenna, down the other side and under the bottom, (still keeping on the same note) and you'll roughly trace the shape of the theremin field, (which is somewhat egg-shaped or, at least, the route your hand takes will be like the drawn outline of an egg sliced exactly in half from top to bottom , (with the narrowest end of the egg pointing downwards).

Where it gets problematic is that if you do the same with another note (say an octave or a fifth higher), then another note another octave or fifth higher, you'll probably observe that the shape alters slightly with each repetition of the "outline", so that the curve in the centre area of the "egg" bulges out a little bit wider each time (with a non-linear theremin like the Etherwave Standard that is; the same experiment with the E-pro suggests a a note-field that's more like a straight-sided sausage ... although they're not precisely egg or sausage-shaped, that's just to illustrate).
Another interesting test is to move your hand in and out from your body (at exact rightangles over the theremin) but keeping it perfectly parallel to the antenna; again you'll hear the note change in keeping with the shape of the note-field.

Anyway ... imagine an invisible egg-shaped note-field. Now, think of each octave-worth of notes like an invisible egg within an invisible egg within and egg etc ... but with the smaller eggs getting narower and less egg-shaped rather than keeping in perfect proportion. Now imagine that sliced in half so you can see the "layers" of octaves ... and the octaves nearest to the bottom of the "egg" are a little more compressed than those in the middle.

That's why fingers a fifth apart on the theremin case aren't really a fifth apart in playing position.

I eventually came to the conclusion that using a practiced/established finger shift of either a fifth or an octave to tune a non-linear theremin worked best ... but only worked consistently if
A) you do the finger-shift at the same height above the theremin case every time (preferably at your regular playing height), and
B) Because the field is curved, even when your hand is always at the same height you must try to keep it the same distance in/or out over the theremin, (again, preferably at your usual playing position) ... and
C) That you always tune to the same note each time, (because the notes/octaves become more compressed closer to the pitch antenna ... so that a

[i]"One problem with you marking the theremin case with two reference points that, when your fingers are on them, give notes a fifth apart ... is that you don't play the theremin on its case. The same two fingers held the exact same distance apart at your regular playing height almost certainly won't be a fifth apart because the note field curves and notes are closer together nearer the top and bottom of the pitch field."[/i]

It does not matter what checkpoint intervals you get, as long as you remember what that interval is when you are in a comfortably tuned field, so that they can be accurately recreated later. The actual playing height intervals will have no resemblance to the checkpoint intervals on the case, but tuning to the checkpoint intervals can help achieve your comfortably tuned field in the future, since both will react the "same" way each time.

The real trick is finding your ideal, comfortable playing field in the first place. Once found, recreating the oddly shaped checkpoint interval that it produces will give you your confortable playing field for next time.

Yes .. that's true. I was merely pointing out that wherever your "checkpoint" is, it has to be at the same height, same place, possibly even the same notes etc each time you tune, otherwise it's pointless, because one place may be a fifth apart, the other something different.

When I first started playing I assumed that an octave jump in one mid-air position would work in any other place mid-air (beside the pitch antenna that is). I suspect that a lot of people who start learning the theremin with enthusiasm, then give up after a week or two, do so because they don't realise the importance of tuning EVERY time they play, and end up frustrated by the fact that they seem to be playing okay one day, then the next day over/undershoot notes quite badly. I know this baffled me, especially when I WAS tuning to an octave jump; it was only when I decided to try tuning to the same octave jump in the same place in relation to the antenna that the frustration lessened considerably.

Actually, I usually "cross-reference" with two different ways of octave-jumping - one in my "comfortable playing zone" the other in a consistent place, (although in mid-air, not on the theremin case).

[i]"I was merely pointing out that wherever your "checkpoint" is, it has to be at the same height, same place..."[/i]

Absolutely. The points pictured in the link above on the theremin should work well. In fact, I would recommend the checkpoints being somewhere touching the case, as this is far more accurate than trying to find consistent space in mid air, which can be more easily misjudged by sight.

Carport888 is right. The ability to adapt is the most important skill in precision theremin playing.

Do not bother trying to solidify your playing arc. It is ephemeral and will remain ephemeral.

One of the things that will develop your ability to adapt is to own more than one theremin (I have six of the things) and to change instruments on a regular basis.

Also, you must remember never to listen to advice from theremin players whose playing you do not like - and that includes, perhaps most importantly, YOURSELF.

Theremin playing is like what sexologist Dr. Ruth once said about sex, "EVERYBODY IS AN EXPERT".

Thank you Coalport, I find that input very useful and helpful. For the last few months I have been wondering whether adaptability was something I needed to focus on. I suspected it was, however, I also felt that I needed to have developed a reasonably solid basis of playing/tuning before I could manage to adapt. I presently have three fairly different theremins, and try to rotate my playing between them - however, I think a few months ago this would've muddled rather than helped me.

I've wondered if part of my slowness to adapt comes from not, so far, having used a pitch-preview. Do you think that helps players be more adaptable by giving them a slight "margin of error" (for want of a better term) out of earshot of listeners? Again, this is something I've avoided so far, in an attempt to get a solid basis first; I suspected that using a pitch-preview too early could get in the way of developing reliable muscle-memory perhaps.

I should add that I certainly don't consider myself an expert ... far from it, having been learning slightly less than one year - however, I'm happy to share my experiences - things that have worked for me - and allow others to draw their own conclusions from them.