Theremin - Performance Technique

Performance Technique

Easy to learn but difficult to master, theremin performance presents two challenges: reliable control of the instrument's pitch with no guidance (no keys, valves, frets, or finger-board positions), and minimizing undesired portamento that is inherent in the instrument's continuously-variable-pitch design.

Pitch control is challenging because, like a violin or trombone, a theremin can generate tones of any pitch throughout its entire range, including those that lie between the conventional notes. And, unlike most other instruments, the theremin has no physical feedback (other than sound), like string tension or the tactile fingerboard for strings, or air column resistance in wind instruments. The player has to rely solely on what is heard, and can only correct a pitch when its volume is not at zero. (Some professional theremin models, including Moog Etherwave Pro, have a pitch-preview feature – i.e. an additional headphone output that allows the pitch to be monitored before the volume is changed.) In the case of some string instruments, the range is divided along the strings by use of length divisions (e.g., frets on a guitar). By contrast, in the case of the theremin, the entire range of pitches is controlled by the distance of the performer's hand or fingers from the pitch antenna in mid-air. Precise control of manual position coupled with an excellent sense of pitch is required, since the oscillator tuning tends to change slowly over time, resulting in changing positions for individual pitches.

Because some portamento is inevitable in theremin performance and because only the most experienced performers can reduce it to an inconspicuous level, the theremin repertoire of beginner/intermediate players is limited to compositions that were written to be performed legato, especially those for voice or continuously-variable-pitch instruments, and in which it is acceptable or even traditional to include some degree of portamento and glissando. Examples of works well suited for performance on the theremin include Massenet's Thaïs-Méditation (originally for violin), Rachmaninoff's Vocalise, and Saint-Saëns' Le cygne (The Swan) (originally for violoncello).

Using rapid and exact hand movements, however, highly skilled players can reduce undesired portamento and glissando to a level enabling them to play individual notes and even achieve staccato effects. Small and rapid movements of the hands can create tremolo or vibrato effects. Although pitch is governed primarily by the distance of the performer's hand to the pitch antenna, most precision thereminists augment their playing techniques with a system called "aerial fingering," largely devised by Clara Rockmore and subsequently adapted by Léon Theremin and his protégée, Lydia Kavina. It employs specific hand and finger positions to alter slightly the amount of capacitance relative to the pitch antenna to produce small changes in tone quickly and in a manner that can be reliably and quickly reproduced.

An alternate and controversial "hands on" technique is called "angling". In this method the pitch control hand is actually set on the top of the theremin, thus violating the "no touch" creed of traditionalists. The performer changes the angle of the hand and fingers to alter the pitch and repositions the hand if the pitch interval is too large for "angling". Touching the instrument damps the effect of extraneous movement on pitch. This permits the use of steady pitches without vibrato and without the performer's remaining perfectly still. An alternate to touching the instrument is to rest the elbow of the pitch arm on a tripod while standing, or the arm of a chair, or one's knees while seated in order to provide a steady reference point and pivot for the arm allowing for steady pitch play over the entire pitch range.

Equally important in theremin articulation is the use of the volume control antenna. Unlike touched instruments, where simply halting play or damping a resonator silences the instrument, the thereminist must "play the rests, as well as the notes", as Ms. Rockmore observes. Although volume technique is less developed than pitch technique, some thereminists have worked to extend it, especially Pamelia Kurstin with her "walking bass" technique and Rupert Chappelle.

Skilled players who overcome these challenges by a precisely controlled combination of movements can achieve complex and expressive performances, and thus realize a theremin's potential.

Some thereminists in the avant-garde openly rebel against developing any formalized technique, viewing it as imposing traditional limitations on an instrument that is inherently free form. These players choose to develop their own highly personalized techniques. Other avant-garde players use strict form and techniques other than aerial fingering. The question of the relative value of formal technique versus free form performances has been hotly debated among thereminists. Theremin artist Anthony Ptak uses antenna interference in live performance.

Recent versions of the theremin have been functionally updated: the Moog Ethervox, while functionally still a theremin, can also be used as a MIDI controller, and as such allows the artist to control any MIDI-compatible synthesizer with it, using the theremin's continuous pitch to drive modern synths. The Harrison Instruments Model 302 Theremin uses symmetrical horizontal plates instead of a vertical rod and horizontal loop to control pitch and volume, with the volume increasing as the hand approaches the plate.