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July 15, 2024, 07:36:10 AM

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Bipolar PSU PA + single PSU preamp

Started by Miyagi_83, July 08, 2024, 06:28:29 AM

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Miyagi_83

Greetings, oh, collective wisdom.
I've got this solid-state guitar amp from the 1980s. It's operational, or at least it was last time I checked, but it's not quite the kind of tone I like. So, a thought of modifying it popped into my mind.

I was thinking of leaving the power section alone and changing the preamp to the one inspired by Joe Davisson's designs switchable to something else. It's not decided yet.

The amp as it is now uses a bipolar power supply and the preamp I was considering runs on a single PSU.
I'm wondering if it's not going to upset the power amp's PSU rail balance due to the extra current draw, which compared to the PA section is minuscule, I know, but it's still there.
Am I being paranoid here?

g1

Probably won't matter, depending how small the current is.
If you are really concerned, you could just put a resistor across the negative rail to draw a little current and balance it out.

Miyagi_83

Thanks, g1 (pentode control grid?  ;) )
I'll measure the preamp's current draw and see how much or how little it is.
Have a good one.