• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

adapting 2 SE boards for a PP driver stage

I want to adapt these SE boards for use as a driver stage for a balanced PP power amp. XLR input for the balanced run and Probally just use an imput transformer to act a a phase inverter for non balanced runs.. I have plenty of power tubes, plenty of output transformers, plenty of power transformers. Have some good sized chasis to do mono blocks. the drive ability of this board, should easily drive 8 to 12 power tubes.

anyone done this before that can offer some insight?


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these look like guitar amps - yes?

Too late - looked it up. Answer - yes. These are guitar amps.

Are you wanting to do hi fi from these?

Thanks for the valid question.

I have Marshall, Peavey, Carvin, guitar amps, and Dynaco, Manley, Shanling, and antique sound USA house amps. I have owned Mcintosh MC2000's, MC2105's, MC275's, Cary CAD-MB50's, etc. My experience is that a good "guitar" or band PA amp, will sound just as good as a good "house " amp.

On these boards. I might change the value of C1 and C2, since I will be using 160 watt transformers that can do 20hz - 20khz. I think on this board, c1 and c2 were sized to limit bandwidth to 5 watt fly wieght transformers.

What am I doing. I want to reverse engineer an amp like the the C#[email protected] V12 which uses SE driver boards as a driver stage. The mono version has 12 EL34's, 2 EL84's (as drivers) and at lease 2 12ax7's. So my thought is if I go balanced end to end, and rely on the XLR connection for phase inverting, I'd be half way there. For unblanced connections I could put in an input transformer to invert one leg of the signal.
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