On Fri, 18 May 2012 08:49:52 +0100, "N_Cook" put
finger to keyboard and composed:

I suppose for this amp only used in 240V land, then replacement SMPS driver
powerFETs only need to be rated 600V/10A and for such an amp only in
100/110/120V land then 300V/20A rating

JP1 in the bridge rectifier area configures the unit for 240VAC
operation when open, and 120VAC when closed. In the latter case the
circuit becomes a voltage doubler.

Therefore Vdc = 350VDC in both configurations.

- Franc Zabkar
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