Tube amp Schematics Index Page - el34world Tube amp Schematics index page There are over 3500 Tube amp schematics and other types of schematics in the EL34World Schematic library. There is also a huge library of effects and solid state schematics. If you see a problem with any of the schematics, please email me so I can fix the problem. DIY Audio Projects Forum • Vacuum Tube Amp Simulation Apr 18, 2019In case anyone is interested, there is a free student version of PSPICE that is available for download. It has a limit on the number of components that can be used in a circuit model, but from what I've read most tube amps won't exceed the limit. It's an awesome tool IMHO to test out a circuit before you build it, and it's FREE!