Attack, attack, attack, attack, attack, attack, attack is what we lack.
A Brief History of Staccato
The pitch circuit of the theremin was developed first. Before Theremin devised a circuit for the volume loop he made instruments that had a pitch rod, an expression pedal and a hand held mute button, an "articulation regulator". These also featured in similar instruments that were developed elsewhere.
On this web page, Peter Pringle describes this in a bit more detail, and provides a short sample of music made with a modern theremin and a simple hand held articulation regulator. http://www.peterpringle.com/ondes2.html
In this video, Martin Taubman plays his theremin variant.
Development of this theremin variant was continued in Russia by Theremin's assistant, Kovalsky. The Kovalsky theremin has a pitch antenna and an volume pedal, and the articulation regulator has developed into a panel of switches to control various aspects of the sound, including staccato playing. In this video, Olga Milanich plays a Kovalsky theremin.
Mention should also be made of Pamelia Kurstin's staccato loop technique (as she calls it. It is more commonly referred to as "walking bass".)
My Experimental Experiments
I have explored variations in my recordings on the various approaches that have been used, with varying results.
This was the first, using an etherwave theremin and a home made articulation regulator held in the pitch hand, and using both the etherwave antennas. I also tried holding it in the volume hand it was confusing - it definitely seems better not to have these two different volume functions - expression and articulation - with two control devices - in the one hand. Having the articulation regulator in the pitch hand was an encumbrance, and would conflict with aerial fingering techniques. For my purposes I found it usable, but limiting.
I have also experimented with a Kovalsky style arrangement, fabricated from a conventional theremin and a soft modular synthesiser running on an iPad mini which acted as the control panel with a USB MIDI expression pedal connected to it. I do not have any recordings of this, as I was very unsatisfied with it. I found relinquishing the volume loop in favour of a volume pedal too limiting. In my opinion the volume loop is as important to the theremin as the pitch rod. (Perhaps even more so - a volume only theremin is a very limited device indeed, whereas my experiments with controlling the volume of a fixed volume instrument with the volume loop of a theremin leads me to feel that the volume loop is a useful tool in itself. (Specifically I ran the output from a stylophone - a very inexpressive instrument with a crude sound through the volume loop of my etherwave (thanks to Thierry, who modified it in a way that made this possible) and it was a vast improvement on the unadorned stylophone. No recordings - I have no stylophone skills worth sharing.)
I have also tried staccato volume loop technique, using my Kees Enkelaar theremin, which has a particularly snappy volume loop. In this video it is the "bleep" sounds, not the noises, which are not from a theremin.
I have also experimented with an effects pedal called a Chopper. This modulates an audio signal with either a sine wave or a pulse width modulation wave (a square wave with variable mark space ratio) or a combination of both, the speed of which is controlled via a treadle. With some settings it "chops" the sound into regular pieces with brief silences in between.
Finally, I have a thin wire attached to the near side (player side) of my volume loop that extends onto the body of the theremin, where it is held down with gaffer tape. This provides a very small portion of capacitive field where I can tap out a staccato rhythm. Iy can only be used for playing quietly, because of its proximity to the volume loop. It can be heard occasionally in this recording.
Theremin Staccato Pedal
My idea comes from the simple observation that many musicians, and people in general, are very comfortable tapping out a rhythm with their foot. Indeed you can even get literal stomp boxes - little foot drums, nice wooden boxes fitted with contact mics, preamps and audio out sockets. http://www.log-jam.co.uk/logarhythm-mk3.html
So it seems reasonable to keep the expression functionality in the expression pedal, and assign articulation to the foot, reversing the arrangement of the theremin variants.
I want articulation to be achieved with a capacitive sensing system rather than a mechanical foot switch for several reasons - a switch by itself is very "clicky" - it requires additional circuitry to provide some envelope shaping rather than just blunt on and off. This would have to be preset. With a capacitive sensing plate, just as with the rod and the loop, there would be subtle variations introduced by the player. If there is magic in the theremin, it lies in the interaction between the player and the capacitive fields. And it would allow the player to move his or her foot away from the plate and continue playing.
It also seems reasonable to me to have the capacitive field operate in the same way as the volume loop, so that the closer the foot gets to it, the quieter the sound, so that playing it means punctuating a continuous sound with brief silences, rather than being able to tap out very short notes. And also so that the player can move his or her foot away from it and continue playing. Other than that, it should have a topology suited to articulation - i.e. a very small, very snappy field - the opposite of what is required for expressive loop playing.
Mention should be made of the Z-Vex Probe range of effects pedals, which have a capacitive sensor in place of a treadle controlled potentiometer. The tremolo in particular (http://www.zvex.com/trem.html) is quite close to what I envisage. (Except that it introduces distortion, which I do not want, the volume logic is reversed and tuning the antenna comes with a warning not to do it!) The Probe range leads me to think a device such as I describe is feasible. I would very much like to hear from the electrical engineers amongst us on this point.
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