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Old 02-06-2008, 04:38 PM
Peter Lindemann Peter Lindemann is offline
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Join Date: Apr 2007
Location: Liberty Lake, Washington
Posts: 1,192
Which one is Better?

Originally Posted by lighty View Post
Sound-wise PWM modulated Tesla coils should sound better, have more precise scale reproduction and wouldn't exhibit any hissing when no signal is present (since it would be turned on). Simply said one has much tighter control over it's sound parameters.

I heard only PWM modulated Tesla coils first-handedly so I cannot rightly compare it's sound quality to Dollard's RF AM modulated coil since I only heard latter on the low quality BSRF video. However, none of these coils are high fidelity devices or at least none that I heard. Peter might disagree on that one but he heard Dollard's coils in person and I didn't so I might be wrong.

This thread reminded me- what happened to the parametric transformer generator concept? It was an interesting concept.

First of all, I don't know if Eric's audio modulation was AM or PWM. He always drove his large Tesla Coils with vacuum triodes in a "push-pull" PWM mode. He certainly had the knowledge to do it either way. The RF carrier frequency was the resonant frequency of the coil, which usually fell just outside of the AM band, in this case just above 1.6mhz. You could easily pick up the music on a short-wave radio in the room, which we did, but the music sounded better coming directly from the flame. The fidelity of the sound above 5khz was as good as the finest tweeter speaker system ever made. The clarity was stunning.

The hiss of the discharge was probably below 3 db. It wasn't much. There were no visible changes to the electronic flame when the music was made louder or softer. The flame was about two inches tall and about one inch wide at the top.

We are definitely stretching the limits of my memory, here!

You say you have seen a BSRF video of this! Where? To the best of my knowledge, this film was never released.


Last edited by Peter Lindemann; 02-06-2008 at 04:41 PM.