The Polyplasmic Arcophone (“Arcophone” or more colloquially, “Mr Zappy”) is a MIDI-controlled, 30,000V electric plasma arc instrument.

More info as this quinessential musical accessory to every mad scientist's laboratory takes shape.

The Arcophone has, in at least one of its incarnations performed at

• Euchronia 2010
• Australian Hackerspaces Meetup at HSBNE.
• Spiegeltent @ Perth Fringe Festival 2011
• Analogue to Digital 4, 6th March 2011
• Analogue to Digital 6, 14th August 2011
• The Harvey Lion's Nutty Professor Expo, 22nd October 2011
• Artifactory residency @ Northbridge Piazza, April 2012

• 12 voices provided by automotive ignition coils & Musical Coil Driver circuits
• MIDI in optoisolator
• Arduino Mega clone clone running our MIDI processing and spark trigger signal synthesizer software.
• One ATX power supply

• MIDI control via Arduino - Note on and off only at present, MIDI note stack, Voice allocation heat-load distribution algorithm
• Custom polyphonic digital pin oscillator (because arduino's tone function is mono! boo!)
• Variable duty cycle (to strike the arc on higher notes)
• Pitch bend
• Vibrato

• Proper antennae for the arcs!

• Voice stacking + detune
• Choreographed voice allocation modes, selectable by MIDI CC.
• Frequency dependent duty cycle (to help charge the coils for the higher spark rates)
• Velocity sensitivity by recruiting extra coils for notes
• Mod wheel support

20th October 2010: