1974 Davoli Orbach B3 - 60W hybrid EL500 amp

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modman
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Got it dirt cheap, completely underestimating the size of the thing.

I did not find any mention online of Davoli Orbach B3, but it seems to be very close to this Orbach 50

It has an preamp using SN76131N, and what I think is a buffer using a BC109B. The power section seems to correspond to this schematic:
Davoli Orbach power.gif
I did some minor work on it, replacing some exploded caps in the preamp. It sounds amazing, but maybe this is just me learning that I like closed cabs? The only problem is a very noisy guitar channel, but after dabblin' with this thing for a day or two, and missing the preamp schematic, my money is on the absence of an input resistor. Bass/organ input has 220k (i think) mixing resistors on the input.

Didn't want to mess with it too much, I may redo the complete preamp with something more interesting.

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vintagekiki
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