Breaking in speaker cables??

I have never noticed volume making a difference for cable break in.

Stick one end of each cable in positive side of ac outlet make sure you tape other end so you don't get zapped. You will be putting 115 volts through cable. That is the fastest way to break them in.

Louder means higher voltage. You might try it. It works for me when I (re) solder terminations, but the break-in only takes a 1/2 hour of medium volume playing.

One European cable manufacturer "breaks in" his UNterminated wires by using them as a main cable for a few hours (on a lamp bulb if I'm not mistaken). That's 230V, 50Hz AC.

DON'T DO THIS unless you're an electrician!

Just mentioned it to give an idea of what crazy things we people will do. A cable cooker is more benign & much more expensive:)

Do you need a electrician to plug in a lamp in a wall plug? Just tape the bare end to be safe.

There is no, "positive" side to an AC outlet. There is a HOT leg, and NOTHING will flow, if a wire is connected between two hots of the SAME PHASE. Current will only flow if a NEUTRAL is attached, or if both HOT legs of your incoming 230V service are attached. In either of those cases; there had best be a load connected(ie: lightbulb/230V appliance), else you will have(of course) created a dead short.