If you use a set of resonators, they will 'talk to each other' and the result will be a broader but lower peak in performance. Useful but not 'peaky'.

So your saying having a set up like this - I guess it would look a bit like a church organ - would result in a wider, flatter power curve, yes?

Although, interesting, its not really what I wanted to know, but thinking about how the Fourier Transform works out - here my maths is real rusty, but I think each sine component should have be a frequency multiple of the first wave (ie. harmonics of n=0). On this bases at fixed RPM all waves should be tuned to one length (if the sawtooth model is valid)...

What I was considering was if say the sinusoidal components can be separated then pipes with (super-fast) valves in could be tuned to derive useful work without causing back pressure (as a turbo does for example).

It would be almost unimaginably complex, but as a theory is it correct?