Interconnect Break In?

@jasonbourne71 " What does change over time is the contact resistance of the connectors due to oxidation.” +1

Simple unplug-plug the same cable changes contact resistance dramatically! Always check your contacts under microscope of just magnifying glass, what you’ll see might shock you! Contact surface is another problem, often “gold plated” contacts are much worse than pure Cu, due to high resistive metal under it (Ti, Ni etc). I found recently couple of very good Rhodium plated receptacles and plugs, showing very low interconnect resistance, and no scratches after use! Remember as contact established by two parts, thus these parts should match in terms of plating metal, ideal metal pressure etc. 

Cables from resistance standpoint are getting worse with time. Dielectric (bad one) hardens and changes Er/TanD after few years of use, which significantly degrades phase velocity flatness across audible frequencies. The lower dielectric constant is, the better! Shorter audio cables have less audible sensitivity to phase velocity than longer ones. 

I’m glad I read this thread because it reminded me to check all my cable contacts. It’s been a while since I’ve done that. For whatever reason I’m not one who can hear differences between cables, except in extreme cases, like interconnects or speaker cables that are very long and too high in resistance. Another case was some cables with a little transformer built in to convert pro level output down to consumer level. Those things sounded horrible. They also measure poorly. Another thing that can sound really bad is using a y-splitter. Very obvious stuff. Comparing two interconnects of any cost that are both meeting basic criteria and suitable for the application has proven mission impossible for me. I also can't tell if it's been broken in or not. 

I've heard that if you eat a bag of M&M's, then wait 150-200 hours and come back and eat another bag of M&M's they will taste different than you remember them tasting 150-200 hours ago.

GHD, that’s great advice. Thankyou. I should’ve just put these on a spare NAD receiver I have and let it run. I was too impatient and put it right into my system. I may move it but that involves moving a cabinet.

JEA- Its a CJ tube preamp. Any idea of whether that is still ’on’ in standby?

Logistics - I have had the same problem. Especially when I switch from plain to peanut M&M’s 200 hours later. 

@ddrave44 the preamp does not need to be on for the cables between cdp and pre to break in because the signal is flowing from your cd player or streamer and passes thru the output interconnects whether your preamp is powered on or not. This is the easiest set of cables to break in.