[linux-audio-dev] Re: Cheby amp code

[Steve Harris]

On Tue, Nov 05, 2002 at 01:56:21 +0100, Tim Goetze wrote:
> >> > For the record my current guess for an amp process is:
> >> > 
> >> >               .-> bandpass -> shaper -.     .--- LP <--.
> >> >               |                       |     v          |
> >> > input -> EQ? -+-> bandpass -> shaper -+-> delay -> EQ ---> output
> >> >               |                       |
> >> >               `-> bandpass -> shaper -'
> >> 
> i do think that the in-cab echo is part of the impulse response
> if you have a convolver ('imp_1199', 'unmatched') following the
> shaper summation node. it sounds to me like it is fwiw.

The impulse includes the cabinet response, but the IIR version you
produced I'm not so sure about, I'd have to run the IIR through octave to
find out I guess, but (looking at it simplisticly) I dont think the
response is long enough to include the cabinet effect.
 
> how many split bands do you think we'll need?

My guess is one for every two octaves. But that is absolutly a guess.
What is the frequency range of a guitar amp? If its more than 8 octaves it
might be neccesary to widen the bandpasses past two octaves, or maybe the
top end can just be lightly shaped together.

Who'd think one small wooden box could be so complicated ;)

- Steve