So your using a Voltage regulator

[Shoog]

So your using a voltage regulator to get your reference voltage.
I tried using a choke in the same position but there was such a marginal effect that I took it out.
unfortunately I added the Cap mult as an afterthought and so the wiring is not ideal. It sits on a heatsink above the big torodial transformer.I put down all of the residual hum to dodgy wiring.

Shoog

 

[Shoog]

Sorry that post makes no sense !!

Thats because it was a mistaken post. Should be part of another thread.

Shoog