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RE: Got one more amp finished to an initial degree.

Posted by kbsp on July 8, 2016 at 08:48:51:
Hi,

Bypassing have been long term best practice for us amateurs but I'm not too sure that it's a good idea after all.

Real world capacitors are capacitors with unavoidable small inductance and resistance so we should design our circuits with that in mind that they indeed are resonators at a given frequency.

By paralleling (different values) of capacitors might interact with each others like a parallel resonant circuit. Our perception of an improvement by the added capacitors might not be an improvement after all. Verifying the implementation by measuring the circuit before and after can give us a hint.

So, I believe your intention by replacing the originally 150uF capacitors is the better approach.

For my own DIY M60 I've installed 4-pole electrolytic capacitors followed by electronic chokes followed by polypropylene capacitors. No bypassing.
It does measure excellent for sure but is it really a better implementation soundwise compared to Ralphs approach? Maybe, maybe not.

Ralphs passive PSU design is guaranteed to be long stable solution without any risk for a meltdown of the output tubes nor our beloved bass drivers.

BR.