If somebody is interested in going (far) beyond the level of a distortion pedal particularly for guitars, I want to mention the best resource I am aware of; the book Designing Audio Effects Plugins in C++ 2nd Edition by Will Pirkle. More precisely, the special chapter 19 addendum on his site, the Wicker amp combo, “a complete tube amp simulation from input to output with reverb”.
I don’t know yet enough about the daisy platform to know if it can be implemented on one I’m actually curious to figure that one out. It would be a cool project. Currently it is a plug-in with an interface, so changes would be needed. However, the main strength is actually in the algorithms. As an EE he has a thorough understanding of the circuit and behavior of tubes/valves.
The code is in the ASPiK download zip. ASPiK is his framework and it’s not needed to look at the code. The good stuff starts in plugincore.cpp
bool PluginCore::processAudioFrame(ProcessFrameInfo& processFrameInfo)
You’ll see the level of detail he went to in order to mimic the behavior of triodes. It’s pretty impressive.
I set up his ASPiK and RAFX7 environments with all the samples and I played my guitar through this amp plug-in (plus another third party speaker cabinet simulation). It sounds very realistic.
I think it’s the best, and to my knowledge the only open source code out there that shows how tube simulation can be done for guitar amps. For somebody who is into this stuff, this one project is something that can be studied, assimilated and experimented with for a long time.
Disclaimer: I am not in any way associated with Will Pirkle and/or the project. I’m just a guitar enthusiast and DSP novice who is excited about this stuff.