Pre3 box & PCB

[novalves]

This is prompted by a startling change in the sound (for the better!) in the Pre3.
I had the PCB screwed down in the middle and at the socket end. I added 2 more supports at the edges - middle and vol control end. Imaging improved significantly - and much more clarity to the sound. My wife noticed this in the other room with the intervening door closed! Another odd thing is that CD seems to benefit a lot more than vinyl.

Pre3 changes
1. 6 (or even 8) supports - in the4 corners of the PCB and in the middle at the edges.
2. Threaded holes for support feet. The glue-on feet migrate in the heat and leave glue tracks (like snails).
3. Harder (?) screws for the cover - I had to drill one of mine out when it got chewed.
4. PSU earthing post could be smaller, then the PCB could be lower, then taller caps would fit. The PCB could be a lot smaller too then there would more room for other stuff, eg. 12v relay
5. Schottky diodes for PSU. Replacing the high voltage ones seems to have given me a much more rhythmic bass.