Monoblock power amps same dedicated outlet?

As long as you are running a awg 12-10 gauge Copper 15-20 amp  breaker circuit then no sweat your amps and preamp should be on the same line anyway to prevent ground loops  no way you will trip a breaker unless you have super low impedance speakers blasting in the 100+ db spl region. I owned a Audio store for years and rarely seen issues with big amplifiers speakers unless very unfriendly loads to 2-1 ohm like the old Apogee ribbons your amps have plenty of capacitor storage capacity to have plenty of reserves on demand just  make sure your dedicated line is a awg12 or lower, lower # = bigger gauge.