A singing Tesla coil makes sound by modulating the spark itself. The arc is the speaker — air is heated and displaced at audio rates, so the note you hear is plasma, not a driver moving a cone. It’s the loudest, least practical and most thrilling synthesis method ever devised, and essentially nobody gets to play one.
Nikolator, from Hügelton Instruments, is a software instrument that models it.
What it’s actually modelling
The distinction that makes this interesting: Nikolator does not use conventional oscillators or samples. It’s a physical modelling synthesiser that simulates:
- the resonant circuit
- the discharge
- and the resulting sound in the air
That third term is the unusual one. Most physical modelling synthesis models an instrument’s body — a string, a tube, a membrane — and treats the air as a neutral medium the sound travels through. With a Tesla coil there is no body. The air is the resonating element, so modelling the atmosphere isn’t an optional refinement; it’s where the sound comes from.
Why model something rather than sample it
You could sample a Tesla coil. ArcAttack, the Austin group who have been performing on solid-state coils since 2005, have plenty of recorded material. Sampling would be cheaper and, for single sustained notes, more accurate.
Modelling wins on the things a sample can’t do:
The instrument is nonlinear and its behaviour changes with what you ask of it. Spark length, discharge character and harmonic content all shift with pitch and amplitude. A sampled coil at C3 tells you nothing about how it behaves at C5 played quietly. A model interpolates because it’s simulating the mechanism rather than replaying a result.
You get parameters that don’t exist on a keyboard. Once the resonant circuit is a model, its component values are controls. You can build a coil that couldn’t physically exist, or drive one past where a real one would flash over.
It’s playable. A real musical Tesla coil is a high-voltage device requiring a Faraday cage, hearing protection and a tolerance for ozone. There is a reason this instrument has perhaps a few dozen serious practitioners worldwide.
The lineage it belongs to
This sits in a specific and appealing tradition: modelling instruments that are impractical, dangerous or extinct. Physical modelling’s most interesting applications have never really been the violin — which is better sampled, and better still played — but the instruments you can’t otherwise reach. Historical instruments nobody has heard, hypothetical ones, and machines like this where the physics is spectacular and the access is nil.
It also arrives days after we covered Suzanne Ciani’s Buchla Cookbook going free and Electric Atlas’s West Coast semi-modular for iPad. The through-line is worth naming: software’s most useful role in synthesis right now is providing access to instruments and methods that are otherwise gated by money, scarcity or in this case voltage.
Nikolator is available via Hügelton Instruments on itch.io. Pricing and release status weren’t published at the time of writing — check the itch.io page rather than trusting a figure from us.