Watch a oneTesla Musical Tesla Coil using a Quad-Arduino ProMini MiDI Interrupter play Toccata & Fugue in D-Minor with a giant arc. All music you hear in the video is coming from the high voltage arc itself. This was recorded in my electronics lab in my basement, which, as you can tell, is a bit cluttered.
If you look to the right of the coil, you'll see a compact fluorescent lightbulb on the table that happens to glow with the high voltage arc discharge.
Voltage-wise, it takes about 30,000 volts to jump an arc between 1 cm. This little coil can create arcs in excess of 2 feet -- you do the math.
Recorded February 26th, 2015.