BACKGROUND
The beginnings: Shepard tone, Barberpole illusion, Risset rhythm
Like the Helix concept, these sound phenomena of the family of auditory illusions - which originally come from electronic music - are based on the synchronization of swelling and fading rhythm / glissando streams, which are played at different speeds and create the impression of seemingly eternal speeding up or slowing down. So far, however, this has been almost exclusively examined only on theoretical level.
Background / history
The Helix concept expands this phenomenon of an acoustic illusion, first discovered by the French composer Jean Claude Rissen at IRCAM, which gives the listener an impression of infinite accelerando (or ritardando) of a rhythmic pulse.
J.C. Risset himself attributed the basic idea to the US artist Ken Knowlton.
Similar to the so-called "Shepard Tone" (= infinitely ascending / descending glissandi - by Roger N. Shepard), the "Barberpole / Risset Rhythm" supposedly endlessly speeds up / slows down the timeline or tempo of musical events...
A visual analogy can be made with the Penrose Stairs as well as with M.C. Escher's stairs (Ascending and Descending)
In contrast to conventional, traditional forms of music, the entire music flow in the Helix system has no fixed, stable basic tempo.
This seems very unusual compared to traditional playing habits: All musical parameters (pitch / melody / harmony / dynamics / timbre) are - based on simple or multiple accelerandi and ritardandi - speed changes (either with speed jumps or with apparently infinite direction of advancement).
In the basic form, using minimalist rhythm structures such as sinus waves or simple beats and patterns, fractal, self-similar elements are first used to create the effect.
Complex forms
The Helix concept extends the basic idea to a diverse, multi-metric composition and playing concept that can be implemented in the practical instrumental context. It can be challenging for the composers as well as interpreters and conductors to acquire this new playing practice and the adapted notation and to internalize them. However, the extremely ambitious approach for the recipient for the musicians involved creates a so-called compression effect (accelerando) or - in the event of a ritardando - a kind of constant braking effect.
In more progressive Helix systems, metric overlays are continuously used and combined and recombined. Furthermore, several - even opposite - helices can be overlaid (Multi Helix).
The Helix system can be applied to any style and enables extreme variety in compositional application.
The concept has been implemented in various contexts since the beginning of 2022.