Piezo Electric Musical Instruments

All sound is vibration.

Typical microphones amplify sound waves. Contact microphones work differently. A contact mic is made of a piezo — a thin brass metal disk with a circle of piezoelectric crystals in the middle. When the crystals are made to vibrate, they produce an oscillating voltage. Speak into a contact mic and nothing will happen, place a contact mic against your throat and it will pick up the vibrations as you speak. The results are like listening to a purely tuned radio. However, when a contact mic is placed on a vibrating surface a hidden and surprising world of sound is revealed — a kitchen whisk sounds like a harp.

This project is an exploration of contact mics and how to build an instrument that enhances this effect. Connecting this to a guitar amp put the sounds collected out in the open air. Research into guitar pedals revealed a handful that enhanced the sounds collected. Here are the instruments.