Power Consumption (Watts)
600 watts 8 ohm 1100 watts
75 watts 8 ohm 750 watts
Note the data plate on the back says ,
120V 60 Hz 1100W
http://www.bryston.com/PDF/Manuals/7B3_Manual.pdf It’s not a question whether you can plug them both into outlets fed from the same 120V 20 amp dedicated circuit. The question should be how will they preform? Will they be starved for power if they are pushed hard any where near their full rated available output power?
What is the distance, length, of the 20 amp dedicated branch circuit? (Up, down, over, and around.)
What size of AWG wire did you use? Bare minimum #12awg or #10awg?
If you used #10 you should be fine if the length of the branch circuit is not too long.
If the branch circuit wiring is #12awg and the length of the branch circuit is over, say 50ft or so, then when you push the amps hard playing music with a lot of dynamics you may experience fluctuations in the AC mains voltage. As the amps are trying to draw more current, amps, (in gulps), to replenish, recharge, the electrolytic capacitors in the DC power supplies the mains voltage will/may dip. A power amp’s power supply need a steady state voltage. It doesn’t like the voltage fluctuating with the beat of the music.
You could use a volt meter and watch the meter as you push both amps hard to see if the voltage is holding steady or fluctuating, bouncing all over the place. You might even try a table lamp using a 60 watt incandescent light bulb. If you see the brilliance of the lamp changing with the beat, dynamics of the music, when you are pushing the amps hard, then that tells you the voltage is fluctuating as the amps are trying to draw more current.
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