loihi
electronic sound and light sculpture, 2021
+12V, external power supply
200mm x 200mm x 200mm
loihi is a mixed-signal circuit containing two microprocessors, two digital-to-analog converters, four digital potentiometers, a voltage controlled low pass filter, and an audio amplifier. The external power source is internally converted and regulated to both -12V and +5V in addition to the +12V input for use in op amps and digital circuitry. The task of each microcontroller is different: an ESP32 produces four audio rate square waves while an Atmega 328p controls the digital circuitry as well as sending interrupts to the ESP32 for frequency changes. The four square waves are mixed down and sent through the low pass filter and a 2.5W amplifier. The pitches of the square waves are tuned using just intonation.
