Is a single 20 amp dedicated circuit enough to run mono blocks

I have the 7b3 into the 20 amp circuit,,,ran it for a couple of hours no issues yet

Have the c2300 pre into a 15 amp circuit dedicated
Vpi classic 2 and ubp 205 and monitor into another 15 amp outlet dedicated

Did pop the wire of one of the drivers,took a while to find the problem,will solder and all should be good to go

I ran a dedicated 20 amp to my 2-channel room when we built our home.  At time of build I was using a McIntosh MC452 and eventually migrated to a pair of PS Audio BHK300 mono's.  I had them plugged into a Shunyata Hydra-6, which was plugged into the Nordost QX4; which was plugged into the wall.  No problems and I often listen to it loud, very loud...when the wife wasn't home.

Thanks for providing the additional info. The speakers have rather low sensitivity (84.5 db/2.83 volts/1 meter) per the SoundStage measurements, but as you indicated their impedance is high (10 ohms or more aside from the upper treble area, where relatively little power is usually required).

I see also that the manufacturer recommends amplification in the range of 20 to 350 watts per channel. So you probably won’t ever be using more than around half of the amp’s power capability, or the speakers would be over-driven and probably distorting or compressing noticeably.

So I suspect that the amps will function in a reasonable manner when powered by the single 20 amp line you’ve described, assuming no other high current devices are on that line. But as Jim (Jea48) indicated, sonics might not be quite as good compared to having a second line.

To put that into perspective, the two amps are specified as consuming a combined total of less than or equal to 160 watts at idle, and if we assume say 1600 watts at the maximum power level you would be using that is a fluctuation of 1440 watts, or 12 amps at 120 volts. The 80 foot total length of the 12 gauge hot and neutral runs in your wiring from the breaker panel corresponds to a resistance of about 0.128 ohms. 0.128 ohms x 12 amps corresponds to a voltage fluctuation of about 1.5 volts. Not a huge amount, certainly, but perhaps enough to have perceptible consequences depending on the energy storage of the amp and the dynamics of the music.

Good luck with the new amps and the new house! Regards,
-- Al

https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=7&cad=rja&u...


Ohm chart for speaker

New house ,using 12/2 wire at 40 feet from distribution box,,great idea with the lamp

Speakers are Focus Audio FS-788,i believe that they are 10 ohoms 

Chances are you'll be ok doing that, but not necessarily. It depends on the speaker impedance (the higher the better), the speaker sensitivity (the higher the better), and your preferred listening volumes (the lower the better).

Each of the two monoblock amps is rated as follows:

Max output power into 8 ohms: 600 watts.
Max output power into 4 ohms: 900 watts.

AC power consumption, 600 watts into 8 ohms: 1100 watts.
AC power consumption, 900 watts into 4 ohms: Not specified, but certainly a good deal more than 1100 watts.

AC power consumption, 75 watts into 8 ohms: 725 watts.
AC power consumption, 75 watts into 4 ohms: Not specified.

So if the two amps were delivering 75 watts into 8 ohms the total power consumption would be 725 x 2 = 1450 watts. 20 amps at 120 volts corresponds to 20 x 120 = 2400 watts, so you would be ok in that situation unless other things on that line drew a lot of current. But you might have a problem if the amps are required to supply power levels approaching their max capability.

Regards,
-- Al

Never seen those, looking at the manual from Bystron they consume 1100 watts, your breaker should be just fine. Looks like they come with a breaker built into the switch, doesn’t say any rating. BTW, bet they’re going to be some outstanding amps.
http://www.bryston.com/PDF/Manuals/7B3_Manual.pdf