2015-2016, ferrous metal, wood, acrylic, electronics, electromagnets
In addition to the robotic percussion and player toy piano, the “magnetic membranophones” in particular featured in “The Magnetosphere” are an underexplored area of musical instrument design and sound composition. They produce a range of rich acoustic timbres similar to horns, cellos, flutes, and percussion.
Using software and electronics, the electromagnet that is held next to each membrane is carefully controlled with pulse width and frequency modulation. Unlike speaker transducers, the resonating objects in this system do not need to be physically touched by the actuator. The magnetic and frictionless setup allows listeners to hear more of the object than its actuator.
The musical score, programmed into the electronics, manipulates the physical sonic character of each specific instrument including resonance, pitch, noise, dynamics, and reverberation. Unlike speaker-based electronic music (one-dimensional sound sources), all of the warm and complex harmonics of the multi-angle resonators on the instruments are projected in every direction (three-dimensional sound sources).
Below is a flow chart that briefly explains the sound process.