On Mon, Oct 28, 2002 at 05:53:26 +0100, Tim Goetze wrote: > >make interesting non-linear filters by using different parameters for the > >different halves of the wave cycle. This is what makes the gong sound > >gongy (waveguide_nl.h). It could also apply to cone modelling, as the > >characteristics of the deflection in the positive and negative directions > >will be a bit different. > > it's interesting to know that valve preamp stages should have > a small bias (to + iirc), and you can in fact observe this in > the amp output i've recorded.
That is a side effect of class B amps IIRC. I would have though that preamps would be class A, but maybe not. > i'm still trying to model the hard-driven valve in the time > domain. the more i look at it, the more i think the 'building of > potentials' i've tried to describe comes near it. though it would > be nice to base it on hard facts about valve amp behaviour, too. 'building of potentials'? Are you refering to your sinc summation idea? Its a nice idea, especially as you get anitaliasing for free, but I think it will be hard to turn a hardish clipping shape into a sum of sincs. > interestingly, the sine, shaped by the hard-driven amp, looks > a lot like the plots of 'ion conductivity' and 'Aktionspotential' > from human heart analysis. Woooosh. [that was the sound of that going way over my head ;) ] > >Different amplitudes would be equivalent to how you model nonliear systems > >with FIR impulses - I can't believe I didn't think of it before. > > in fact you described something along these lines a few days > ago. ;) Er, did I? Right. Maybe more sleep would be good ;) - Steve
