How long for IC cables and Power Cords to break in


I recently replaced all my interconnects, power cord for my power amp, and a Monster power center. The first pass in listening did not produce any real improvement. I shut the system down for about a week to let the wife watch her "Swan" and "American Idol". Then I turned on the system last night. Suddenly everything sounded different. Brighter, more detailed, wider sound stage, bass powerful.

Do wires break in themsleves as long as current goes through them or is there a rule of thumb as to how many hours before one reaps the benefit?

System- B&K reference 4420 power amp
B&K PT3MK2 preamp
Adcom 600 CD
Vandersteen 2CE sigs
XR interconnects
Siganl cable power cord for the power amp.
Thorens 160 c with Linn basik arm and linn K5 cartridge. (Goldring 1012 on the way to replace the Linn K5...
eagleman6722
Idid just what Darrylhifi suggested. I was breaking in two P/C's and long speaker cable runs. I think when I finally turned everything off, it was 114 hours later.
Guys, it's more about the changing dielectric distortions with "exercising" the insulation, either by running lots of signal through the adjacent conductors, or "curing" it otherwise. I've developed such a "curing" process for Teflon insulations that results in no burn in curve. Some insulations can actually take months...even years to finally cure otherwise. That's why AIR is the best dielectric, next to a vacuum. Teflons (and other fluorocarbons) are third.... Ern
"Dielectric distortions?" Has anyone ever been able to measure this "distortion?" Why not? "Curing" the dielectric? Any evidence that either the wire or the dielectric go through any changes whatsoever?
Guys we are answering a post , where the guy shut down his system for a week so his wife could watch "The Swan" . If he reaches for the vacuum I have a feeling it wont be for cable break in. The Swan is all pretty now, Let the music Play !