120v vs 240v


Doing a electric panel upgrade and thinking of running 3 new dedicated 8 gauge circuits, 2 for possible future 240 v  ( which can also be 120v) monoblocks and a dedicated 20 amp for other gear
What are the pros and cons of 240v  vs 120 v for amplifiers

also how many isolated ground circuits do I need?

 Thanks 
digitaljoseph
240 volts allows for smaller wire sizes since the amperage draw is cut in half for a given amplifier power consumption rating at 120V. Since you are using #8 wires you are negating the main advantage going to 240V.


 I would recommend 2 30amp dedicated circuits using #3 10 gauge wire.  With both receptacles will be dual voltage: top plug 125 volts 30 amps and bottom 250 volts 30 amps...running the amps on 230 volts increases the dynamics of the amp, transient response, and lowers the noise flow.  No speaker cable I ever tried made that difference... 
just a thought... 
ditusa6
I would recommend 2 30amp dedicated circuits using #3 10 gauge wire. With both receptacles will be dual voltage: top plug 125 volts 30 amps and bottom 250 volts 30 amps ...
That’s problematic for several reasons. First, you’ll likely need to use a special receptacle for that 120VAC 30A line, because many local codes won’t allow a conventional 15A or 20A receptacle on a 30A line. So the receptacle you’ll be using won’t be compatible with the plugs on your equipment.

The 240VAC 30A line will also require a properly rated receptacle. Again, that likely won’t be compatible with the equipment’s existing male AC plugs.

And you are not going to find a duplex receptacle - which is what you’re describing when you refer to a "top plug" and a bottom plug - with different configurations between the two plugs.
Consult an electrician to get advice based on the codes in your area. I can't figure out what you're trying to do. Figure out if you want 240v amplifiers or 120v first. 
CLEEDS the the plug that is needed is a leviton 5842-i i have 2 in my home in stall by a electrician 125v 20amps top bottom 250v 20amps my amps run on 230v to run 125v change the power cord thats it 230v powe cord is a nema-6-20p to c13 iec my amps see the voltage from 100v to 250v no change of the amp is needed