We have 240v here and its very stable, the actual voltage will be a symmetrical 30.65v, but the difference between 340mv and 500mv is only about 0.02w so I wont bother with the lower forward voltage diodes.
Yes I do mean 33,000uF it is a multichannel class A amplifier so the more the merrier, if I use a PP film cap for Cin would it still need to be 4.7uF or different?