The Electric Knife Orchestra
The Electric Knife Orchestra consists of sixteen knives and one meat cleaver (all purchased from the $0.99 store) that have been brought to life to perform the Bee Gees’ 1977 hit Stayin’ Alive. The orchestra consists of six musical machines and all of the sound is created through the operation of these machines.
All of the instruments are controlled using one Arduino running firmware based on code available online here. The music was arranged in Logic, output using a USB to MIDI cable and then read by the Arduino using the MIDI circuit that is detailed on this page.
There are two machines that create sound by stepping stepper motors at the same frequency as musical notes. The Jacob’s Ladder uses a relay to control a 12,000V neon sign transformer and the three other machines work using MOSFETs connected to solenoids and car door lock actuators. Apart from the Jacob’s Ladder, the whole installation is powered using a computer PSU. The machines themselves are mainly constructed of transparent acrylic and were prototyped using aluminium extrusion and then designed in a vector graphics program and laser cut.
You can find an Instructable on how to build the Jacob’s Ladder here.