Building A Plasma Piano Ain’t Easy

Electronic arcs can be made to “sing” if you simply modulate them on and off at audible frequencies. We’ve seen it done with single Tesla coils, and even small Tesla choirs, but [Mattias Krantz] took this to extremes by building an entire “plasma piano” using this very technique.

The build relies on ten transformers more typically used in cathode ray tubes. The transformers are capable of generating high enough voltages to create arcs in the air. The transformers are controlled by an Arduino, which modulates the arcs at musical frequencies corresponding to the keys pressed on the piano. Sensing the keys of the piano is achieved with a QRS optical sensor strip designed for performance capture from conventional pianos. For the peak aesthetic, the transformer outputs are connected to the metal hammers of the piano, and the arcs ground out on a metal plate in the back of the piano’s body. This lets arcs fly across the piano’s whole width as its played. Ten transformers are used to enable polyphony, so the piano to play multiple tones at once.

Building the piano was no mean feat for [Mattias], who admitted to having very limited experience with electronics before beginning the build. However, he persevered and got it working, while thankfully avoiding injury from high voltage in the process. This wasn’t easy, as Arduinos would regularly freeze from the noise produced by the arcs and the system would lose all control. However, with some smart software tweaks to the arc control and some insulating panels, [Mattias] was able to get the piano playable quite well with a beautiful chiptune tone.

It bears stating that HV work can be dangerous, and you shouldn’t try it at home without the proper understanding of how to do so safely. If you’re confident though, we’ve featured some great projects in this space before. Video after the break.

[Thanks to Dr Jon for the tip!]

17 thoughts on “Building A Plasma Piano Ain’t Easy

  1. I used to work in a High Voltage Research Lab. 1.8 Million volts and 300,000 AMps of 60 cycle power. I loved is and hated it because of the dangers. We would set up a test and the folks in production would come running in reporting big arcs on the shop floor. I could not watch this video to the end.
    But a good real life example of high voltage projects.

    1. There was quite some risk assessment in the background.
      If you’re interested, you can find more information on his discord, but the main takeaway is, that the arc frequency was kept quite high ( I think around 35kHz), and galvanically insulated from earth and ground.
      (So its basically an HF HV source (with flyback transformers) Wich got modulated by the tone frequencies.

      Also there was not one Arduino but one Arduino per coil/Driverboard

  2. Rugged Chips makes some, well, reinforced industrial Arduinos. Mostly upgrades to the input pin side? Not cheap though nor do they even do any of the newer ones which seems sort of odd. I think there is a MEGA at least but that is not exactly new?

    Looking at their site, a bunch have screw terminals too which is also nice. Anyway, would something like that have helped here at all or it would have just jumped across that anyway?

    Every I/O pin is protected by a 5.1V zener diode and 220 ohm 30mA PTC (resettable fuse).
    Every I/O pin can have up to 24V applied to it and will still not be damaged (only 10V for the Ruggeduino-ET).
    Every I/O pin can be short-circuited to ground and will still not be damaged
    Every I/O pin can be short-circuited to another I/O pin and will still not be damaged

    As an aside, why do official Arduino boards not do this basic kind of “if it sends more than this much current, it will just fry things” so it has the hardware to at least limit that? The RPi CM4 is just as bad with their standard “test” board. Save a few cents times each board?

    1. Arcs can very much produce musical tones. Here is Doom.

      To quote the authors; for those who did not understand what is going on this video, here’s a brief explanation: The main loud music really comes from the tesla coil sparks. They are literally playing the music due to the programmed phase, pulse width and firing frequency! So, there are no speakers, no audio / video special effects. It looks even better in person and sounds almost the same, just louder than people expect!

    2. Years ago when I was an apprentice electrician one of the tradesmen told me about when he worked for an AM radio station a vine grew on the guy wires of the transmission tower causing an arc to form.
      Apparently you could hear the station perfectly playing through the arc.

  3. My grandfather used to build pianos for Euterpe around the Pfofeld area of Germany after WWII. If he were alive, I bet he would be enlightened by the ideas, but would lose it when it came to the disassembly of the soundboard and the “cutting of the strings.” Very cool to see this being done, and the testing process to make it work. ;)

  4. Lmfao, holy Christ I can’t wait for people to send this article to Mattias. For those that might be wondering what he’s doing right now, he’s currently building a GAS-POWERED GUITAR. Y’all should check him out. He doesn’t have the energy of a madman like Michael Reeves does, or the sarcasm of I Did A Thing, hell, not even Backyard Scientist could ever do such a thing like this, but Mattias sure as hell could top all of these guys off in the music industry.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.