Tube Amp Archive

I had a copy of the hand-drawn schematic, but must have deleted it.

Could someone email me a new copy? bolinskey at indstate.edu

I built an inspired-by amp with the basic Express circuit, a Lar-Mar PPIMV and a GZ34 rectifier.

It's one of my favorite amps.

Thanks. I removed the NFB wire from the impedence switch and the squeal went away. Then I swapped the blue/brown wires and tested teh amp. Still no squeal, so I reconnected the NFB, and.....



NO SQUEAL!

I'm good, now.

I'm pretty sure that everything is wired correctly (I've gone through it twice), but will go back through it again.

I'll check the 1987 wiring and see if that does the trick, too...

I've built an amp loosely based on a Trainwreck Express/Komet/Weber Java. Basically a Trainwreck circuit, but with tube rectification, and a Lar-Mar PPIMV. The amp sounds good, but I'm getting a horrible squeeal from the Presence control (it's interactive with the PPIMV, as well). I've poked around ...