TONE is an analog audio feedback circuit with a tree-like array of three electret condenser microphones, resonant 4Ω loudspeaker, 9V amplifier, and cylindrical waveguide. Acrylic 'leaf' microphone mounts are suspended at the end of each cylindrical 'branch.' Acoustic feedback is situated by arranging the loudspeaker upward toward the mic array. As pressure waves propagate upward from the loudspeaker, sound is filtered through the pipes before arriving at the mic array, thus introducing non-linearities and expressive opportunities.

In Spring 2019 Jeremy Wagner set out to build a piano resonating device for upcoming research projects and performances by CNMAT composers.  This work draws heavily on prior design work by Per Bloland, et al. with some improvements specific to upcoming CNMAT projects.  The design brief called for a device meeting the following criteria:

BLOOM is a flower-like analog oscillator on a transparent substrate comprised of three piezoelectric transducers, one transistor, one 3V battery, three LEDs, three photoresistors, and three resistors. Configured in a feedback loop, the circuit self-oscillates and produces variable light/sound sequences. The transparent substrate and stem-like conductive trace design gives each component an aesthetic quality. Photoresistors on the piezo elements provide subtle interaction by changing the electrical resistance when light is more or less present.