Originally Posted by WelwynNick
I've gone mad, and acquired another 861 for experimentation.

Proper dedication!

Now are you going to have the linear PSU inside the 861 or in a separate enclosure for further improvements?

I remember experimenting with power supplies for an external phono amp (using Naim boards), on paper it only needed 0.1A of current per board.
I went from 0.5A to 1A and then to 5A per board, sound quality improvements were easily heard each step.
The best and final power supply I used was made up of Yuasa sealed lead acid batteries (peak current of about 20A), measurably better as there was no ripple* as there was no 100Hz capacitor recharge cycle.

Good luck and have fun!

Steve.

* ripple in the power supply is easily heard as low frequency hum, especially important when your circuits are amplifying microvolt signals from phono cartridges.