Distilled wisdom regarding AC mains for home studios suggests noise and hum are best subdued with all audio equipment on one circuit, perhaps even a single receptacle.
 
At some point, you will exceed the current capabilities of home use 20 amp breakers and wiring, what then?
 
How do larger studios set up wiring for different rooms? Are there bigger breakers and wiring techniques to allow for more equipment, or better grounding techniques to allow the use of multiple circuits without penalties of additional noise?

Most studios will use power conditioners just in case.  Though usually any properly wired building will not have ground loop problems.  20 amps will get you well over 2000 watts of power, plenty for everything in most modest studios.  Though there shouldn't be a problem adding a second circuit either from the main box or splitting a 30-40 amp circuit breaker into two sub panels for separate rooms. Usually the ground point will be shared by everything.  

I'm tempted to say something, but I think I should wait for Bill (wst3) to explain it so he doesn't have to waste time correcting my mistakes. :-)

rumleymusic
Most studios will use power conditioners just in case.  Though usually any properly wired building will not have ground loop problems.  20 amps will get you well over 2000 watts of power, plenty for everything in most modest studios.  Though there shouldn't be a problem adding a second circuit either from the main box or splitting a 30-40 amp circuit breaker into two sub panels for separate rooms. Usually the ground point will be shared by everything.  

Thanks, Daniel.
 
I have 3 circuits in play presently.
 
One, 20 amp, original house wiring for the west end of the house, three bedrooms, a bath, and the west walls of the living and dining rooms.
 
Two, a 20 amp home run installed recently solely for audio use, one two duplex receptacle, feeding a chain of fair to middlin 6 ways, tiered for easy on/off in banks.
 
Three, a 20 amp home run installed recently with a single duplex in the tracking room, and another in the control room adjacent.
 
I need to get meters inline to see what I'm drawing now, and also get a few pieces of audio gear off circuits 1 and 3.
 
I have a  Chauvet light board, several LED parcans, and a DMX transceiver pair on circuit 3, along with a drum machine, bass processors and a wireless receiver (for bass) on circuit 1, but so far, the only noise problems I have are in a pair of Lexi MX200s (which are fed by a send from main interface, with guitar amp signals present) which are analog but headed for fully SPDIF implementation soon....
 
...some noise issues between tracking and the remote laptop dock, which turn out to be unbalanced 25' runs, coulda swore I laid balanced TRS cables in there, gremlins done it.
 
...and some 60 cycle hum in the new control room, which has the PCs on house wiring circuit one, and audio racks on studio circuit two.
 
Think I can resolve most or all the issues easily, but before I do, I need to know how much is already on circuits two and three, and what my options are if I bump my head on either, with ideal configs from a noise POV.
 
You've given me options there, and I appreciate it, thanks!

This feels like a setup!

I'm actually working on rewiring my studio these days, so this will be brief...
 
As has been pointed out - short of a large console or tape deck, or large amplifiers a 20A circuit will probably handle all your needs. But since you asked: "How do larger studios set up wiring..."
 
The current general wisdom suggests that a sub-panel be established, here in the USA it is referred to as a separately derived service, and that has connotations, I'm sure, but I am not a licensed electrician, so I leave the code issues to those who understand them fully.
 
aside - one thing I know for certain is that if you design your power system to be safe it will be quiet, whereas there are ways to design for quiet that are not safe!
 
aside - ground loops always exist! They are not always a problem, but they always exist. The term ground is often misused. Ground ought to refer only to the earth, and an earth ground is used only to provide protection from lightning or power grid faults. It plays no part in noise reduction. The neutral is bonded to ground at the service entrance because neutral is usually the return leg, and if it is compromised, or if an energized conductor somehow energizes an enclosure we want an alternate, very low impedance return to ground.
 
I was trying to be brief, wasn't I?
 
So, in a large facility a separately derived sub-panel provides "technical power" for all devices that might have an effect on the audio. If the facility is really large the sub-panel will have both legs of the single phase that feeds the building, but a single leg can be used. And multiple phases can be used, but that gets really tricky.

Power conditioners - be wary of power conditioners! Depending on the technology employed they can be the single largest contributor to studio electrical noise!
 
Surge protectors - there are two kinds of surge protectors, series mode, and stuff that doesn't work when you want it to<G>. Avoid the inexpensive surge protectors that simply strap MOVs across each line to ground.
 
In my last purpose built studio I used four breakers from the "A" leg to power everything but the console, tape decks, and amplifiers. All of the outlets were Isolated Ground outlets, and I went one step further and brought an insulated ground wire from each outlet back to the breaker box ( this was easy since the panel was in a work room adjacent to the studio space - I would probably never do this again though<G>!)
 
The big power items were all powered from a separate pair of breakers configured for 220VAC. This was an experiment, partly to see if halving the current would have an effect on magnetically coupled noise (it did), and partly to see if there was anything to the "Symmetrical Power" concept (there is.) Most studios today don't have equipment that requires that much power, so it's probably moot.
 
Does this answer your question?
 
And Mike, next time feel free to jump in ahead of me!

:-)
 
There's an irony for me. I did some remodeling a year and a half ago. I pestered my electricians to give me a three outlet box with a dedicated 30 amp circuit for my rack and CPU then a small change in room layout, after all the paint and trim was finished, caused me to disregard that specific circuit and plug the whole shebangs into a general purpose 20 amp circuit serving the other wall outlets.
 
Best laid plans...
 
:-)
 
My home setup only has a 200 amp max house panel capability and it gets spread thin between the house, the studio, and the work shop stuff. I don't know much about power wiring in commercial facilities, other than it can be dedicated and doesn't have to be constrained to a 200 amp max mains connection. 
 
best regards,
mike
 
 
 

Buy the fact Jay Tee used the term "mains" I have a feeling he is from the UK or some other location other than North America. The rules are different and so is the way they wire things, apparently.
 
I owned an commercial building and built a new addition that became my small studio.
One thing about the music community. It will always contain someone of each trade. Bernie was an "A" ticket electrical and a hell of a good guitar player too. He had worked on huge industrial sites as well as the hospital.
It was no big deal to wire the studio. As long as you do a solid job of installing everything and keep all motor loads on the other phase.  Like Fridge and A/C. We had a very quiet system and there were at least 6 breakers just for the live room. This is mostly for running a bunch of Tube amps and there was a PA system too.
I sort of remember that all outlets were on one side of the phase, and all lighting and motors the other. It had elecric baseboards which are 240V so used both phases.
 
He told me people have issues in certain locations because the Delivery system or sometimes the Transformer is funky.
 
I had a bunch of custom made surge strips made by a tech friend of mine. He took standard power bars ( metal ones) and added a sh-t load of big a-s Caps in there. I still use those.
My studio is at home again in my original location I put together before I bought the commercial building. I built this house myself and did all the wiring. I ran a special circiut and kept it on the "clean side" of my panel. It's only  15 Amps but that's way more than a home studio will ever use. Only Tube amps draw any sort of power. Monitor system might be next on the list. Modern computers and LCD screens use very little power.
 
PS- here in Canada you can't have a 20 amp breaker on a standard outlet. All duplex type outlets have to be 110V - 15 Amp. # 14 guage wire. 12 outlets per circiut.
 
There is a special plug for 20 amps, One prong is sidways. And the wires feeding it will be #12.
It's possibly totaly illegal to instal a 20 Amp outlet anywhere but in a workshop. Don't quote me on that. The rules are always changing, and getting more uptight. Bedroom bedside  outlets have to have these $60 breakers that kick out if you knock your lamp over.
 
 

boy...I'd put #10 wire on that 20a outlet, especially if it's on the other side of things.  But I want to say, here in the US, you can only put one 20a outlet per circuit... but I'm a non-licensed electrician, that sees a lot of generator "backfeeding" into their house system, thru such type outlets, here in Kentucky.  (remember to shut off your mains...right!)  That typically also give you some "hot prongs" on that generator cable as well.  Great for young kids.
 
I've got a question though... what are the thoughts of using a UPS power supply as a "voltage regulator" and minimal surge arrestor, as compared to these glorified Furman "power strips"?

I'm in the US. Many 20 amp breakers in the box, and electrician didn't blink adding 3 more. (One for the pond pump and lights outside.) I'm learning all kinds of good stuff here, so feel free to continue discussion at length
 
:-)

mixmkr
boy...I'd put #10 wire on that 20a outlet, especially if it's on the other side of things.  But I want to say, here in the US, you can only put one 20a outlet per circuit... but I'm a non-licensed electrician

This is not true... The NEC requires a receptacle to be rated at 20 amps if it is the only receptacle on a 20 amp circuit. You can have several receptacles on a 20 amp circuit. The rule of thumb for residential guys is 6-duplex receptacles, for the guys that do the math it's 180 va. If you install more than one receptacle on a 20 amp circuit they can be rated at 15 amps. 
 
Rocky