Bogen CHB35 Mods and Preamp ideas

[gtrbryan]

I acquired a Bogen CHB35, which is virtually identical to the more common CHB35A but with a tube rectifier. Schematic is below

http://us.f13.yahoofs.com/bc/441c56eem1623d0ba/bc/Public/Bogen+CHB35+Schematic.pdf?BCrDuFFBnQXXzMkZ

I first plan on replacing the caps, which needs to be done, and of course wire the input jacks and output jack for guitar.

I am thinking of modding one triode of the 6eu7 (V1). That way, I can have two distinct sounds out of this amp, essentially making it a two channel amp. Any ideas? Does anyone see any problems of modding one triode like a fender preamp stage. Would this give too much gain with a total of 3 preamp stages? The second two look like they are wired pretty cold. Maybe a GA5 preamp stage?

Any help is appreciated.

 

[Enzo]

FOlks convert these all the time.

Go to Schematic Heaven and there is a section on old PA amp conversions. Might find some good stuff there. And a million schematics too.