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[TCML] tcs as musical instruments...

As I was driving to my daughter's rehearsal this afternoon, I thought about Bart's videos (and all the other musical TCs).. and realized that we should think about what kind of instrument a TC is, and my best guess is that it's sort of like an organ that can play only one note at a time.

There's not much in the way of dynamics. You have to have enough "bang" to get a breakout, and the sound from a small spark is not a lot different from a big spark. So it's like a pipe organ in that way. You get big changes in volumes by adding ranks of pipes.

Can it do polyphony.. I think so, in a limited way. You're basically generating a pulse stream. And I could logically "OR" two pulse streams, one at "C" and one at "E" for instance, and I should hear two notes. Easy to test with some .wav files

How many octaves range does it have.. you can go pretty low, but the loudness will drop off. The bang size is roughly constant, so the acoustic power as the rep-rate goes down goes down with frequency, and Weber-Fechner law means that lower frequencies "sound" less loud for the same power. What's the top frequency, maybe a couple octaves above middle C?

Can we make a TC put out a sound that's different than the sort of buzz we normally get. Perhaps, if you send closely spaced double pulses? What does something that is, say, bang, 1 ms, bang, 9 ms, bang, 1ms, bang,... sound like.. Yes, about 100Hz, but there'll be some interesting harmonic structure that would sound different. Then there's all the old techniques from early synthesizers: Two pulse trains at the same frequency, one with a bit of FM on it (a sort of vibrato/tremolo effect)

But here's the intriguing thing.. I've always wanted to build a setup with multiple TCs that can do real polyphony. Originally, I had ideas of multiple rotary spark gaps a'la a Hammond organ and tone wheels (someone actually did this at the turn of the 20th century, I have found).

And, because I'm a spark gap kind of guy, I started building a multiple triggered gap.

but these days, the DRSSTC is SO much more controllable.

If you could control the RF phase (which I would imagine you could, with clever timing), you could phase multiple coils so that sparks would preferentially strike between toploads.

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