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Power from Wall

I am moving from 2 channel to 5.1 home theatre and will be adding several amplifiers. I am concerned that my single dedicated 15 amp circuit will not provide sufficient power. I am trying to calculate the electrical draw from all of the amplifiers to see if an additional 20 amp circuit would provide sufficient power. I seem to find limited information on how to do this calculation.

My main speakers are Genesis V (4 ohm imp, 90dB), uses a toroidal transformer Class D Servo Amp (400W/CH) to drive the woofers and I use a separate YBA2 amp (150W) for the mid and highs. I am also using a separate ultra-efficient 500W Class D discrete MOSFET switching amp for a Genesis S4/8 sub. I also will be adding another 200W amp for the rear speakers. I also am using a Panasonic 65ZT60 plasma, that has a rated power consumption of 620W and average power consumption of 189W.

I have been told that I need around 45-60 amp service to the outlets to run this system. I want some headroom so the various amp have plenty of power, but a requirement of 45-60 amps seems like an awful lot of power and question if it’s really necessary.
joe11554
yogiboy's avatar
yogiboy
5,630 posts
 
A 15 amp circuit will handle 1800 watts, a 20 amp circuit
will handle 2400 watts. What you have now is sufficient. No
possible way would you need 45-60 amps. If the circuit
breaker does not trip on your new system you should be
fine,if it does then you would have to upgrade to a 20 amp
circuit. 15 amps x 120 volts = 1800 watts. 20 amps x 120
volts = 2400 watts.
rlwainwright
1,904 posts
 
You should be okay with your current (heh, heh) service. If the breakers don't trip, and I really doubt they will, you're good to go. I would go ahead and install the system and see how things play out...

-RW-
jafant's avatar
jafant
19,408 posts
 
I concur w/ Yogi-
I will add this question;
are you living on a grid or off? (example: living in a major U.S. city) Keep us posted and happy listening!
joe11554 OP
29 posts
 
Thanks for the assistance.

I am on city service, Naples FL
It didn't make sense to me either, their explanation
is the Class D amp is only 30% efficient so you need considerable more power. I thought the purpose of Class C was their efficiency?

I was also thinking of putting a Torus Power AVR20 on the line. Saw them at NY City show in Brooklyn show recently and their approach made sense. Can I put this unit on a 15 amp line or would it be time for a new 20 amp line?
yogiboy's avatar
yogiboy
5,630 posts
 
That is for a 20 amp line. They make one for a 15 amp line. I explained the reason a 20 amp circuit(overkill) would be needed,but if you want to have one put in you will have to have your wiring changed to 12 gauge. Sounds like it's time to call an electrician.
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