Tube DIY Asylum

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RE: Increase L in pi network

Posted by Chip647 on September 22, 2017 at 05:43:42:
Do you have too much B+ ripple?

Typically you want just enough filtering to make an amp acceptably quiet. If it is quiet, adding more filtering is not usually good for sonics. If you are using high quality caps and chokes, bigger ones are way more expensive.

If you have hum, most of the time it is not from the B+ rail unless you are using a poorly designed filter.

FWIW, A filter of 40uf-4H-40uf-4H-40uF @ 100mA to 200mA will be quiet and good sounding. You can get reasonably priced 300mA rated chokes that will be mechanically quiet as well. For highish current power supplies, high inductance chokes are not always better sounding.