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.