A solid state rectifier is more efficient, so the B+ voltage will be higher than with a tube rectifier. This can be a problem in the Sunns because the filter cap can is only rated for 525v DC, and even with the tube rectifier, the B+ stock is over that. My 200S runs at 560v at idle. You can change the amp over to use discrete series-connected caps instead of the cap can and get a 700v or more rating in the first three cap sections easily enough, and then you could use a solid state rectifier safely. Another option is to use the Weber Copper Cap rectifier, which is a solid state replacement that emulates the tube rectifier as far as lowering the voltage the same amount and also emulating the sag characteristics of the tube rectifier.
A more normal solid state rectifier will also allow the amp to control voltage demands better, so it stiffens up the power supply and makes the bass tighter. Going to the larger filter caps will do this too, which is great if you are using it for a bass amp.
Greg
