Interactive Music Instrument, Custom PCB
Noise Guitar
This is an experiment in making a musical instrument.
Date
2022 Spring
Related Course
Homemade Hardware
Instructor
Andy Sigler
Design & Developer Tools
Eagle CAD / Circuit Board Schematic Design
Arduino / Programming
Bantam Tools Milling Machine / PCB Milling
Inspired by Otamatone, this is an unconventional electronic musical synthesizer. I try to make it a fun noise generator with multiple ways of controlling it, using different kinds of sensors and being able to change with multiple toggle switches.
Design Process
For the microcontroller, I used the ATMEGA328P. I try to use the reading of multiple sensors, like photocells and a soft force potentiometer to control different aspects of the sound. Since the reading of some sensors is not always stable, like the photocell, so I add in potentiometers. Then I used multiple toggle switches to switch the reading between sensors and potentiometers.
For the audio, I used the Mozzi Library for the audio generation. And the audio output, I also added a toggle switch to switch between the internal speaker and external audio output.
Noise Guitar circuit design file in Eagle
Noise Guitar PCB design Front
Noise Guitar PCB design Back
Noise Guitar PCB design
Prototyping
Before starting milling the PCB board, I prototype it a few times with Arduino and ATMEGA328P chip on the breadboard. Then I milled out a few versions with a Bantam Tool CNC milling machine, with my little logo engraved. There were multiple failures due to being unable to burn the bootloader, but luckily it was fixed by changing the libraries used and also the chip model.
Circuit testing on breadboard
1st PCB Prototype
PCB Prototype version 3 to 5
Next Step
This initial test successfully demonstrates an interactive sound generator. So far, I've integrated the audio output with Ableton and channeled real-time audio data into TouchDesigner to manipulate visual effects based on the audio produced by the noise guitar. For future enhancements, I plan to combine the Noise Guitar with other audio synthesizers to enrich soundscapes and visuals.
Noise Guitar Audio to Abelton to TouchDesigner