2. tech-talk
  3. 1413586582

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
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
20,535 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
5,907 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.
joe11554 OP
29 posts
 
Agreed, that way I have plenty of headroom for processor, CD, DVD, tuner, etc which I didn't include in calculations.

I have opportunity to get a used AVR 20 at a lot less than new, but have some concern over getting used for that type of product.
More to discover