Crackatwoa film cap upgrades

larcenasb · 2405

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Offline larcenasb

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on: February 21, 2023, 11:24:02 AM
Hello all,

I know the Crackatwoa circuit does a better job than a standard Crack with all the usual power supply upgrades (choke, Cree Schottky diodes, bypass caps). But what about changing the last power supply cap to a film cap that matches the output film caps (as I and many others have done in the standard Crack)? And maybe putting in a 470uF electrolytic in place of one of the other power supply caps to make sure there’s enough PS filtration? I remember PJ saying the last power supply cap is part of the “output current loop” and should theoretically be as important as the output caps in terms of how the amp sounds. I think that’s the gist of it, but correct me if I’m wrong.

Right now I have two ASC 60uF output film caps, so was thinking of buying a third for the last PS cap, and a 470uF electrolytic as one of the other PS caps to pick up the slack of using a lower-capacitance PS cap. And advice is appreciated. Thanks!

Lowell B.


Offline Paul Birkeland

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Reply #1 on: February 21, 2023, 12:28:23 PM
The Crack-a-two-a has shunt regulated power supplies that isolate the raw power supply from having to handle signal currents, so these caps are not at all crucial in the C2A compared to the stock Crack.

Paul "PB" Birkeland

Bottlehead Grunt & The Repro Man


Offline larcenasb

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Reply #2 on: February 21, 2023, 01:42:22 PM
Ah, okay, thanks Paul! I’ll start rolling just the output caps with those removable leads in my build. Cheers!

Lowell B.