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Digital Emulation of Tube Amps

Started by nanmoniz 6 days ago2 replieslatest reply 3 days ago117 views

Hi guys, I'm doing some research work on emulating tube amps digitally and I'd appreciate any help you might be able to give me. I was looking into the Wiener-Hammerstein model and Wave Digital Filters to implement a digital amp in a Teensy 4.0 but I'm not sure what's the best one in terms of quality emulation and real time processing.

Would you care to give me some insights about this in case you have some experience in this field?

Thanks in advance

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Reply by deanpkJanuary 13, 2022

I took a quick look at A: https://www.researchgate.net/publication/224642046...

which makes a digital version of a tube amp analog circuit, I think is what it does.


And the one B: https://www.hsu-hh.de/ant/wp-content/uploads/sites... a math modeled harmonic structure.


As a user one gets used to certain GUI control parameters - Drive, Gain, OverLoad, Tone - there is also speaker and cabinet emulation sometimes included - so how these are reflected in the chosen model is interesting. The math model will emulate the characteristics of these parameters and the 'circuit' model is using a what?

I might have got the interpretation of each model pretty wrong but that is how they read to an end user like myself.


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Reply by engineer68January 15, 2022

An interesting aspect to mention is also powering, cooling and the situation how a tube is built in which has some relevance according to my investigations. Also the tube driver and load has much impact.

I do not see all these points modelled correctly in lots of these papers and moreover one has to identifa parameters to hand over to the users. This is a wide field of options for individual behaviour of a particular tube.

Therefore I am concentrating on the specific effects I identified with tubes when modelling their behaviour and use parameters which have a musical meaning.

In FPGAs time domain modelling is most appropriate:
http://www.96khz.org/htm/guitardistorsionvhdl.htm

However I started with DSP-Software too in my early days:

https://www.mikrocontroller.net/topic/40054#298767

juergen