Zeusaphone - The singing Tesla coil
Yes, you can make music with lightning. The wonderful singing Tesla coil known as Zeusaphone (sometimes called a Thoramin), is a form of plasma speaker with one-to-one mapping. It is a variety of a solid-state Tesla coil that has been modified to produce musical tones by modulating its spark output. The resulting pitch is a low-fidelity square wave like sound reminiscent of an analog synthesizer.
The high-frequency signal acts in effect as a carrier wave; its frequency is significantly above human-audible sound frequencies, so that digital modulation can reproduce a recognizable pitch. The musical tone results directly from the passage of the spark through the air. Because solid-state coil drivers are limited to “on-off” modulation, the sound produced consists of square-like waveforms rather than sinusoidal (though simple chords are possible).
While early versions of the Zeusaphone generally used zero crossing threshold detectors as a method of producing music through their spark output (an example of this circuit was released by ctc-labs.de in 2009), Scott Coppersmith was the first person to design a complete MIDI-based Tesla coil system. Since then, the systems work by means of a microcontroller that is programmed to interpret MIDI data and output a corresponding pulse-width modulation (PWM) signal. This PWM signal is coupled to the Tesla coil through a fiber optic cable, and controls when the Tesla coil turns on and off.
The term “singing Tesla coil” was coined by David Nunez, the coordinator of the Austin, Texas chapter of Dorkbot, while describing a musical Tesla coil presentation by Joe DiPrima and Oliver Greaves during DorkBot’s 2007 SXSW event. The term was then made popular by a CNET article describing the event. They had been doing public performances with the technology since March 2006. Shortly after that, DiPrima named their performance group “ArcAttack” and became the first musical group to ever use this technology in live performance.
The name zeusaphone was coined after a public demonstration of the device on June 9, 2007, at DucKon 16, a science fiction convention in Naperville, Illinois. The performance was by Steve Ward, an electrical engineering student at the University of Illinois at Urbana–Champaign, who designed and built the Tesla coil he used. Since the invention of the Tesla coil by Nikola Tesla in 1891, never had a Tesla coil product achieved such an incredible level of precision and control as to be able to amplify music through lightning-like arcs exceeding one million volts of electrical potential. Thus, the revolution in Tesla coil technology began with the Zeusaphone.
The term “Zeusaphone” was conceived by Barry Gehm, of Lyon College, on June 19, 2007, in a conversation with his friend Bill Higgins. It is a play on the name of the sousaphone, giving homage instead to Zeus, ancient Greek god of lightning. The name was adopted by Ward on June 21, 2007. The alternative name “Thoremin” was suggested by Dan Butler-Ehle; it is a wordplay on “theremin” incorporating the name of Thor, the god of thunder in Norse mythology.
Believe it or not you can actually buy one of these things and there are several models to choose from, with the largest model ZFX-160 standing at a wapping 7 ½ feet (around 2.30 meters) tall, generating 1.5 million volts of raw throbbing musical electricity. The prices for all models go from around $2,000 up to $8,500.
