Re: [music-dsp] Simulating Valve Amps

2014-06-18 Thread STEFFAN DIEDRICHSEN
That’s a wild theory. ;-) E.g. A Leslie 122 amp has a rather small power supply transformer, which has to deliver B+ and heater voltage. The output transformer is about 1.5 times the size of the power tranny. If it comes to output transformers, the distortion caused by them is rather mild. It

Re: [music-dsp] Simulating Valve Amps

2014-06-18 Thread Tim Goetze
[Sampo Syreeni] From what (very little!) I know of hardcore analog simulations, I'd say that is part of a more general and much nastier problem. That's the interaction one: whereas digital signal graphs have a definite direction of signal flow, there's no such thing on the analog side no

Re: [music-dsp] Simulating Valve Amps

2014-06-18 Thread Andrew Simper
On 18 June 2014 16:15, STEFFAN DIEDRICHSEN sdiedrich...@me.com wrote: Actually, it’s not rocket science to model a baxandall or those Treble/Mid/bass networks. A straight forward approach is modified nodal analysis, which gives you a model, that preserves the passivity of the filter network.

Re: [music-dsp] Simulating Valve Amps

2014-06-18 Thread Tim Goetze
[STEFFAN DIEDRICHSEN] Actually, it's not rocket science to model a baxandall or those Treble/Mid/bass networks. A straight forward approach is modified nodal analysis, which gives you a model, that preserves the passivity of the filter network. Perhaps I was being too vague; in any case, I

Re: [music-dsp] Simulating Valve Amps

2014-06-18 Thread Andrew Simper
On 18 June 2014 18:26, Tim Goetze t...@quitte.de wrote: ... Thanks to the work of Yeh, I personally consider the tonestack a solved problem, or at least one of least concern for the time being. Cheers, Tim A linear tonestack has been a solved problem way before Yeh wrote any papers. Also

Re: [music-dsp] Simulating Valve Amps

2014-06-18 Thread Nigel Redmon
Of course, high gain amps have from four to six gain stages (and the stages may have attenuation). I’m simplifying by putting all the gain in one stage, but the point is that when you’re cranked on one of these amps, you can count on being locked into the hard-clip region of the curve, and the

Re: [music-dsp] Simulating Valve Amps

2014-06-18 Thread Nigel Redmon
BTW, I do know that it was developed with the Sonic Core SCOPE SDK, and I suspect it’s just using fairly routine DSP blocks, with a lot of care in tweaking the sound. (It runs in my mind that I might have seen some block diagrams on a forum back when he was developing it—the point is that I

Re: [music-dsp] Simulating Valve Amps

2014-06-18 Thread Theo Verelst
Once more, you'd have to think about this problem as to include a curtain test (within reason, I mean just to make the point) where you take the optimal example tube amp, place the mic in front of it, put that on the PA or monitoring in another room (or in the same room, to let the guitar