http://bestperformance3.com/?author=39 The Cyclonda is a new electronic musical instrument that transforms audio feedback into a sea of mysterious, resonant sounds. It is currently under development as a prototype. Please check back often for updates, including new photos and sounds.
The principal components of the Cyclonda are a small omnidirectional microphone and a small (< 1W) loudspeaker. By bringing the microphone within inches of the speaker cone, the performer initiates a feedback loop, which is then processed with audio software and played back to the audience in real time.
A brief audio clip generated using a prototype of the Cyclonda
While audio feedback is normally considered undesirable, when transposed down several octaves it has a pure, bell-like tone. Audio feedback results when a sound travels in a loop from the speaker to the microphone, then back through the speaker (via an audio cable linking the two). The quality of the sound is determined by the position of the microphone, construction of the hardware and acoustic characteristics of the space.
The performer uses a computer to manipulate the audio processing of the raw signal while simultaneously adjusting the position of the microphone in relation to the speaker for diverse sonic results. In the current prototype, the microphone hangs over the speaker and can be raised and lowered via a small servo motor and a potentiometer.
The raw feedback signal is subjected to a number of procedures before being played back to the audience, including compression, transposition and reverberation. This process transforms the loud, shrill sound we associate with feedback into a low, sustained sound. Several copies of the raw signal are transposed at different levels in parallel, resulting in a richer musical texture.
Using feedback as an audio source presents several unusual challenges. Audio feedback can become quite loud as a signal is added to itself many times per second. It is also unpredictable and dependent on a number of external factors, many of which cannot be easily controlled. Another consideration is that the raw feedback, while relatively quiet due to the scale of the hardware, must be isolated from the processed sounds played back to the audience.
Yet these challenges are easily surmounted with some clever engineering. The interesting thing about using feedback as a source is that it is a “natural” source of sound. Instead of using samples or electronically synthesized tones, the Cyclonda is powered by a natural physical phenomenon. When you listen to the audio sample above, you hear the tones as well as their imperfections, the resonances and the dissonant vibrations.