Bogen CHB-20A Rebuild

[physics]

Nice pick for an amp to mod!  I've worked on and actually used to buy Bogen's to mod and they are nice platforms. I often used the octal pre-amp ones but did a bunch of 60's ones too.  The transformer generally sound pretty good.  It's a shame they got some expensive to acquire.

I have to agree that the Contertina is probably the best sounding PI too.  I do have a fondness for various iterations Paraphase inverters too but in the stability and versatility department they are inferior.  They sound great though.  To my ear the Concertina are warmer and have more character than the Schmitt.  It is hard to explain that to customers that believe that Fender/Marshall/Vox's PI must be the gold standard but most players I know seem to agree after they've tried both types.

Yeah, prices are a bit stupid now. I got lucky and found a guy who wanted space, so was selling them cheap. Thanks for another endorsement of the concertina! My Peavey VK100 has a concertina in it, and it sounds like it'd be worth seeing what I can do with that instead of trying to rework as a LTP. To no-ones surprise, the PCB doesn't hold up the best to rework.... A shame since space-wise it's fairly comfy working inside the chassis.