Question: Musically useful Theremin ranges. ?

[i]How can you expect so much from Fred M.??!![/i]

This is not what I expect, this is what I would like. I anticipate that over the course of the dialogue I will learn more of what is feasible, and Fred will learn more of what I (and anyone else who cares to join in) find desirable.

I expect the difference between what I want and what I get will be the same as the difference between a concept car and a production model.

Just wait until you hear what I would like in the wave-shaping area! (Pretty much the same as is available on a modern keyboard synthesiser. Mwahahahahahaaar!)


[i]My volume antenna (being worked on at present as a seperate stand-alone unit - but thats an off-topic for this thread) is unconventional - prototype uses a round circular bathroom light housing.. but will have knobs on it anyway...[/i]

Ah yes, the 3D controller thingy. I was thinking in terms of a conventional loop. For a volume-control-only antenna I would want a hole in the middle of it so that I can punctuate phrases by snapping my fingers down and up without worrying about hitting it with my fingertips. My thought about having a mute button was that there would be more than one control I would want access to during a performance without moving my volume hand - to vary timbre, for instance - and would not want them all crowded together next to the loop.

No one who is motivated by profit should waste time making and marketing theremins. The only theremin that has ever made money for its innovator is the Moog Etherwave. When Bob Moog began making etherwaves, it was the only thing his company (Big Briar) was manufacturing.

Subsequent attempts to successfully promote and market more sophisticated and more expensive theremins, even the attempts made by Bob Moog himself, were commercial failures.

I'm not sure how well instruments like the Russian doll, or the Gakken "theremin mini", have fared commercially but most serious thereminists consider these types of pitch-only devices to be toys, and not true theremins. I don't mean this to be a put-down of these types of instruments. Many people own them and enjoy them but comparing your "matryomin" to an Ethervox is like comparing your Casio keyboard to a Steinway.

On the other hand, Casio sells far more keyboards than Steinway sells pianos.

It took Bob Moog a lifetime to come up with the Ethervox theremin, and fewer than 50 units were sold. I doubt that it paid for its own research and development.

Beware of asking the theremin-playing public at large what it wants from a theremin. Expectations will vary considerably and a theremin made "by committee" could well turn out to be a disappointment. In the effort to please everyone, the theremin maker could end up pleasing no one.

In the brief 80 year history of the instrument, the dreams of theremin makers, beginning with those of Lev Sergeievitch himself, have invariably surpassed what the makers themselves have been able to realize.

Even if the ideal instrument is eventually produced, it is unlikely to be done in a single, definitive act. It will be the result of a process of evolution over many years and several generations of instruments.

[i]"No one who is motivated by profit should waste time making and marketing theremins" - Coalport[/i]

I agree on that! Oh, there are sections of the market where one can probably make some money, right down at the low end, selling 2 transistor pitch only "theremin" kits which cost you about $10 and selling these for $79 (+$10 P+P)..

My original motivations did include making some money.. ;-) .. now, if I recover even a tiny fraction of what I have invested, I will be more than happy - I will be happy if I get a good Theremin which a lot of people like (I realize that I cannot make everyone happy - 99.9% satisfaction would probably do ;-) and made enough money to be above the 0% tax threshold.

[i]"Ah yes, the 3D controller thingy. I was thinking in terms of a conventional loop. For a volume-control-only antenna I would want a hole in the middle of it so that I can punctuate phrases by snapping my fingers down and up without worrying about hitting it with my fingertips. My thought about having a mute button was that there would be more than one control I would want access to during a performance without moving my volume hand - to vary timbre, for instance - and would not want them all crowded together next to the loop." - Gordon C [/i]

Hmmm.. How important is the hole in the loop? - I ask this because I have major deviation in my ideas about the volume function.. Wasn't going to discuss these yet.. but..

My idea is to have the whole Theremin 'box' (with all its knobs etc, except for the pitch antenna tuning) doubling as a volume (and in higher units, as a 3d volume / vocal formant / other controller) antenna.. Control over the volume response would be completely adjustable in terms of where null occurs, the size of the control field, and the curve (linearity) of this field.

The idea is that the player would place the unit at a comfortable height, so that the null (sound off) position is about 10cm above the unit. Volume control would extend over the entire box area (say 30cm length by 20cm depth).. and in the 3d version, left right / forward backward movements would control harmonic related functions (similar to a joystick) while up / down controls volume.

The pitch antenna - its a completely separate unit.. it contains variable and reference oscillators, and tuning knob / circuitry / null detector and indicator etc.. The pitch antenna will be on its own separate stand, with a single multicore lead to connect it to the main ‘volume’ – LOL! Unit.

My reason for thinking of this approach had something to do with Peter’s comments re Theremin stability.. I thought, why not just make the pitch antenna ultra stable and wobble immune? .. Players could position the antenna wherever suited them best, at whatever height suited them best, left or right side. Then the idea of turning the control box into a volume antenna seemed obvious… This scheme allows complete freedom to locate the ‘controllers’ for the Theremin how ever one chooses.

I was going to put this idea up for comment before I went ahead with it.. I suppose now is as good a time as any!

Fred.

[i]"Just wait until you hear what I would like in the wave-shaping area! (Pretty much the same as is available on a modern keyboard synthesiser. Mwahahahahahaaar!)" - Gordon C[/i]

how "modern" ? If we are talking about sample playing MIDI synths, it will not be coming from me! .. If we are talking about a CV based analogue synth, the first 'add-on' board I have planned will be a CV board to track over the entire Theremins audio output - up to 9 octaves from 16Hz.

Ok - best if I give an overview of my PLANS (note, these are plans - not promises)..

1.) Core Theremin - Antenna board and 'main' board.

2.) Volume + 3D board (3d Volume board to also be launced as stand-alone product)

4.) C.V. board

5.) Slave control board and SkyWave H1 Slave (a clone of the H1 Theremins at Hands-Off 2010)

6.) Slave control board and EW Slave (a clone of the EW Standard without antenna coils etc - can only be used a slave)

7.) Slaves for other popular Theremins such as the Enkelaar.

(more than 1 slave can be controlled sinultaneously)

Brief overview of the system:
[i]Basic Theremin pitch section consisting of 2 boards - one board at the pitch antenna, and one board taking signals from the pitch antenna board, doing secondary heterodyning (superhet) to shift the frequencies down without losing the magnitude of the difference frequency - then the signals (variable and reference scaled down to about 30kHz) are fed into a pair of custom IC's which contain programmable PLL's and dividers to multiply and divide the frequencies (and resulting difference) for range scaling. (this IC multiplies the ~30kHz to over 40Mhz inside the IC, and then performs divisions and further multiplications to produce non-integer multiples of the original input frequencies if one desires this - as will be needed for the more advanced builds)

I am (in order to reduce cost) only designing one PLL IC, with everything I can imagine I need, and cramming it with everything possible to fit on the silicon.. using serial messages, the function of this IC can be radically altered - without serial messages, it reverts to a 'core' build which is being optimised for my simple version Theremin.

The output of these IC's contains frequencies + difference frequencies which can be taken to more stages of frequency multiplication / division / addition / subtraction to scale them to whatever is required.. Or they can be (as they will be on the low-end version) taken to another (this one only semi-custom.. as in, not so expensive) IC which performs mixed-signal heterodyning and allows DC control of the amplitudes of the audio output signals, and DC control of a pair of low Pass (12db/octave) filters.

The audio output signals from the above are: square wave at Fundamental which has DC level control and voltage controlled LPF following it; Sine waves at Fundamental, 2nd Harmonic, 4th Harmonic and 8th Harmonic.. the level of each harmonic is independently DC controlled, these (the sines) are summed, and the output taken via the 2nd LPF. The outputs from both VCFs are summed to give the audio output.

The DC control voltage from the volume antenna can directly drive the above (via potentiometers to control the harmonic mix), or a seperate VCA can be used (seperate VCA allows preview to monitor the tone mix, without seperate VCA, preview can only monitor the square wave - alas, this is to do with the limited configuration possibilities I have with the IC).

There is also a square wave (no DC amplitude control) and a seperate square wave being output which is a fixed multiple of the fundamental frequency, and which tracks with no added latency - This signal can be used to generate stable, low latency CV's for Theremin audio output going right down to 8Hz* (at 8Hz, the latency is 4ms, at 16Hz it is 2ms, at 32Hz it is 1ms.. etc)..

One little problem with my CV is that it does not work well ab

To me both is fun to play with - the very low and the very high frequencies and of course everything inbetween. If being switchable: just fine.

Maybe out of topic and a little over the top according to the momentary state of your development is just an idea. Sometimes i like to play with effects between the theremin and the amp. A nice feature would be a slot like on old atari consoles where effect devices could be placed into (with power supply and signal in/out, bypass). Which then just could be used with the theremin.. Maybe not that good idea, but kind of goodie and must have, if once the theremin is called ones own.. Anyhow - a ring modulator or a sawtooth tremolo (for percussive playing like with the gristleizer) would be cool stuff if being onboard. If no effects onboard - fine aswell.

I rather like the look of this modular synth module (http://www.cyndustries.com/modules_minimac.cfm). I think something like that would give me the flexibility I would wish for.

(Hahaha. I'll try to talk sense on the subject when it's not off-topic to the thread.)

[i]" A nice feature would be a slot like on old atari consoles where effect devices could be placed into (with power supply and signal in/out, bypass)." - Dominik [/i]

Hi Dominik,

Yeah, it would be nice.. But its not going to happen unless I actually got into mass production with a custom built plastic case with hinged slot cover ...

But you did mention one thing that might be really relevant -

How badly would Thereminists feel about losing the ability to make their Theremins go ultrasonic by touching the pitch antenna? My Theremin is likely to spoil this kind of fun!
;-(

[i]"(Hahaha. I'll try to talk sense on the subject when it's not off-topic to the thread.)" - Gordon C[/i]

Good idea! ;-)

But I dont really want to start another thread right now.. Trying to stay focussed! (and losing the battle )-8

I will check in every now and then - but for now I am going with switchable ranges only.. I am in no desperate hurry to get feedback on the volume / box idea - Probably wont get working on that for a month, and will be doing it for my 3d controller before then anyway - It is only the range stuff I need to finalize quickly.

Fred.

[i]How important is the hole in the loop?
[...]
Control over the volume response would be completely adjustable in terms of where null occurs, the size of the control field, and the curve (linearity) of this field.
[...]
The pitch antenna - its a completely separate unit[/i]

Ah, that would be me thinking about theremins I am familiar with again, where a small volume field (my preference) places my fingers close to the volume loop, and jogging the loop causes the pitch rod to move.

So no, not so important in your design.

One feature that I do like and make use of in the loop configuration is that the extent of the capacitive field is different above and beside the loop so that playing regular staccato above the loop sound different to playing staccato beside the loop, Pamelia style. (Which some people other than Pamelia call "walking bass". Pamelia described the above the loop style at a gig I attended as sounding like "a broken owl".)

I would hope this would still be the case with your design. (And that I could alter the volume response to get an Enkelaar style "bloopy" staccato if I wanted.)


Also "hypersonic tweeting on the pitch rod" is not such a big deal for me. I seldom do it. I'm sure whatever design you finalise on, people will find ways of making it do silly things that weren't really part of the plan.

Actually, I think this effect only really illustrates that people's etherwaves are not optimally tuned. Reading the manual I get the impression that if you tweak the trim coils just right it doesn't happen. I could be wrong though.

O.T.

Hi Dominik. Yay! Another Gristleizer fan. You're right - gristleizer style modulations are great with theremin IMO. Here (http://soundcloud.com/beat-frequency/angel-wings)'s a little experiment where I put a sine-wave tremolo after a delay and varied the speed of the LFO driving it from time to time. It sends shivers down my spine. :-) (As well as illustrating what I meant by "Enkelaar style bloopy staccato" at 59 seconds in.)

[i]"I would hope this would still be the case with your design. (And that I could alter the volume response to get an Enkelaar style "bloopy" staccato if I wanted.)" Gordon C [/i]

If your your Enkelaar I modified can obtain that 'bloopyness' then my new design *almost* certainly can.. With the Enkelaar I was limited by the crude front-end and the abysmal 'VCA'.. With my design I have a linear CV from the front-end, and adjustable 'curve shaper' to give everything from linear (bloopy - as in, rapid increase in volume close to antenna, through log giving a percieved linear response, to X2 giving slow change close to the antenna and rapid increase as distance increases) .. However .. I say *almost* because:

I have not really thought about the field shape arround a conventional loop antenna (aaarrrggghhhh! )-8 .. It is fine and well being able to adjust the curve - but I can see that this is not the same as being able to go from one 'curve' to another dynamically, simply by changing where one is playing the antenna... And I have this horrible feeling that I may have missed something extremely important here..

In my mind, all sorts of solutions are buzzing - my 3d antenna actually consists of 4 volume antennas - the biggest challenge has probably been keeping the volume response constant over the X-Y playing area .. as in, Z does not change as a function of the X/Y position.. This is absolutely critical, because Z is used as an amplification factor for the X+Y values.. The utter irony is that this could work directly against what you have just 'revealed' to me.. I may need to 'dissacociate' the 2 Y antennas, and give each a seperate 'curve', so that one gets a 'bloopy' response if one plays (say) over the left hand side of the unit, and a gentle response playing over the RHS antenna, and varying mixed curves between these..

On the simple unit, I may just use a loop! :-( .. One other reason I thought the 'volume antenna in the control box' was a good idea, was that it would be universal - left handed and right handed players could use it without any antenna swapping etc -- As soon as I have a loop, I need this loop to be re-locatable .. Also, there is great simplicity in having the aluminium foil antennas stuck on the back of an insulating front panel..

Time to put my prototype Theremin back together and try it with a loop antenna.. In fact, its strange - but I have never built any Theremin with a conventional loop antenna! LOL ! Perhaps it has more to do with the fact that every bit of metal I ever try to shape ends up looking like a rotwieler has mauled it. ;-)

Fred.