Stephan Möller AC30Simulator

[teemuk]

By the time you get done messing with something like this you could have easily built a good sounding guitar amp.

What's the fun in that? There's a difference between taking the easy route and building yourself a tube amp according to well-established circuit topologies and designs, or going the hard way and trying to push things forward with new stuff.

[DougH]

Depends on how you define "fun", "easy", and "pushing things forward". That's different for everyone. I'm just offering a different point of view. Besides, I don't think anyone here is trying to "push anything forward". They are crossing their fingers and hoping someone will give them the component values for a design someone else already "pushed forward" with.

Building a tube amp is not "easy" and I shouldn't have used that word. But it is more pleasurable and ultimately satisfying, for me. The hard part of building a tube amp for me is tweaking it to sound and respond just the way I want it when it's built. I'd rather spend my time doing that than spend it trying to get a ss device to behave like a tube. Just get a tube. If you're trying to save money because you can't afford the tube thing then how are you ever going to compare the ss thing to the tube thing so that you know that you're done?

Build ss stuff and make it sound "good". Build tube stuff and make it sound "good". Don't waste time trying to get one thing to behave like something else. Instead, spend time trying to get whatever it is to sound good. But that's just me.

[rezzonics]

I've been working on this AC30 Tube Simulator project for some time, and published the results on my blog. I obtained values by comparing LTSpice simulations of the original AC30 valve circuits and the Stephan Möller circuit. I started by giving credit to his excellent work.
These are the LTSpice simulations:
Tube Simulator - Simulations - Preamp (1/3)
Tube Simulator - Simulations - End stage amplifier (2/3)
I modified the Speaker simulation circuit using Sallen-Key filters:
Tube Simulator - Simulations - Speaker simulator (3/3)

These are the practical implementation posts:
Tube Simulator - Practical implementation - Schematics, BoM (1/4)
Tube Simulator - Practical Implementation - PCB layout, manufacturing, assembly (2/4)
Tube Simulator - Practical Implementation - Chassis, face plate (3/4)
Tube Simulator - Practical implementation - Test, debugging and verification (4/4)

And this is the sound check and comparative with some AC30 emulators:
Tube Simulator - Sound check and AC30 emulators comparative

[mr coffee]

Checked out your pages and sound samples.

The AC30 Tube Sim sounds pretty convincing, although I think I would have turned the tone knobs and maybe added a Top-boost Capacitor switch to get more of the sound that I associate with desireable AC30 tones.

But I have to ask about all the hiss - the background hiss when the guitar riff stops for a second or two is REALLY high. Is that just how noisy the circuit is, or is that related to the way you connected the speaker simulator output into your computer?

Thanks for sharing your work. I wonder how many people missed your post to this old thread that might be interested?

Hope this bumps some views.