Thylacine Dream wrote:So I determine which outlets are common by looking in the box to confirm they're all on one breaker?
I have yet to live in a place that has this listed well enough at the breaker.
Mapping things out can be a pain in the neck. Here's how I do it:
First, I map out the room(s) with respect to physical outlets. In MANY places this is not really required, but sometimes this can be incredibly helpful when troubleshooting stuff like ground loops/etc...
Okay, say you have three rooms with four walls each and one outlet on each wall. Draw this out, it does not have to be dimension accurate. Run over to you breaker box and turn one breaker in the area of interest off.
Now test each and every outlet to determine which ones no longer have power, also test lighting. Now you can mark the breaker number that you shut down next to each and every outlet and light that has turned off. That is a branch circuit, and that entire branch (often having outlets feeding multiple rooms) has a limit to how much current it will deliver before circuit protection kicks in and shuts you down.
This map is important, as I have enjoyed music rooms that happen to share outlets with the kitchen, and could shut down if I was being active while someone else was preparing food. Old houses often have nightmarish branch circuits.
Now, if you have a room that enjoys multiple branches, you can utilize more power at once than in a room with a single branch. I find that by myself this is pretty much a non-issue, but if this is a practice space with a full band, amps add up fast and a single branch can run into overload.
Thylacine Dream wrote:If, say, four outlets in a room are common, does that mean it doesn't matter if the same load is plugged into one or distributed across the four of them? Or is it still better to spread it around?
I do like to assume that each plug into outlet in a branch creates a little resistance, so it is better to have four power strips connecting to four different outlets rather than four power strips in a daisy chain hanging off of a single plug. Most of the time, assuming decent house wiring, the house circuit does not care. However, typical in wall circuits are designed to carry more robust loads than a power strip - which should be thought of as the weak link in the chain. So spreading those out in as evenly a manner as possible is encouraged.
I realize you've got a pretty centralized set up in your rack, so in that I would prefer to fan them out from say, a quad outlet, where each of your four power strips plugs into a wall. But with your current meter it should be easy to determine if you're pushing your luck with anything.
TL;DR, connect the biggest loads direct to wall whenever possible, and fan the smaller stuff out on power strips. Your ultimate measured load will determine how many branches you need to utilize when going all in.
Also, if you have two branches in the same room, and discover everything gets noisy when you're using them both I can provide remarks that might be helpful (I just don't want to load this post down even further).