How much more power do 2 Bryston monoblocks use?

I have an ADCOM 5500 amp right now - 350 wpc into 4 ohms. I’m contemplating moving to Bryston amplification and I’m looking at either the 4b ST or a pair of 7b ST amps. So far, I’m doing very well with my electrical service (15A & basically a dedicated line).  I use Magnepan 1.7s and an ADCOM 555 to power a pair of subwoofers.

I know I have some extra headroom to play with. I use a space heater in the winter with settings of 600/900/1500 watts. I can currently play music with the heater on 1500 watts - no problem. My usual method is to turn the heater on full when I’m warming up the system and then turn it down to 600 watts when I go in and listen.

I’m probably still going to want some heat in the winter, though. 😉

The 4b STs will work, no sweat. Anybody ever run into electrical problems switching to the larger mono amps?

Thanks,
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