3 Nov
2002
3 Nov
'02
7:24 p.m.
On Sun, Nov 03, 2002 at 08:06:53 +0100, Tim Goetze wrote:
yep, it doesn't seem to be getting easier the more we look at it.
the above approach could bring us close, but it does need xfading
and two chebyshev shapers.
We'd also need to split up the incoming signal by frequency though, and
that would make it expensive to run.
i'm not up to understanding all implications of
the fact that the
incoming signal is not a pure sine; neither do i have a recipe for
preparing the coefficient tables -- if we scale the individual
coefficients by 1/sum their mix will not match what we want.
I think we should probably abandon the cheby approach for now, this
combined with the freqency dependency problem probably makes it a looser
:( been thinking about how to do a hard clipper with sinc
some more
today, without real results though.
Yeah, I think thats difficult, and probably not neccesary, the "hard clip"
from a guitar amp doesn;t look very hard to me, so I recon you could just
apply the shaper, plus a bit of oversampling, a LP filter and it'd be
fine.
Remind me: what was the thing that put us off chains of models? Was it
just the messy bottom end? Or was there more? I'm pretty sure I can fix
the muddly low harmonics and it sounds like other people aren't modeling
the variation in harmonic amplitude with signal amplitude, so maybe it
isn't important.
- Steve