I am building one of Randy Slone's designs...Referred to as his favourite amplifier of any type in his Audiophile Source Book. It is rated as standard at 140W into 8Ohms and 200W into 4Ohms. It has been explained how it can be modified very simply to make 300 or even 400W!

I intend to run this at its intended power (140/200W). What size transformer would I need? I know that P=VI and that VA=VI but what about overheads etc. I studied power for a little while and understand there is a difference between VA and W. Is there a rule of thumb?

Edit:

I forgot to ask. I have four transformers (2x500VA and 2x1000VA). Here are the specs of each:

500VA:

2x115V Primary 2x50V Secondary

1000VA

2x115V Pri 2x55V Sec.

After a bridge rectifier per side and two 6800uF electrolytic caps per side, what would the output voltage be? Any ideas?

Thanks

Gareth