What are we listening for during break in?

I'm a "no cable break in" kind of guy too.

I understand speakers (there are physical changes in the cones & surrounds).

Perhaps, I can understand electronics (manufacturing aids flashing off, cap's fully charging, operating temperature changes...).

Don't understand cable break-in...

although a cable's sonic character may change a little over time, the basic 'sound' or 'signature' remains.

There are two issues here, and they are being conflated.

1. Do cables require break-in?
This is unlikely to be resolved for more than a few who have not yet formed an opinion. Lots of sincerity, mixed with disbelief, bombast and outright belligerence on both sides usually emerge on this. Strength of opinion does not equal truth. This, though, does not seem to be what the initial poster is asking.

2. What "sonic differences" are heard? "Better, worse, different?"
These were the questions here. The answer seems conmplicated and simple.

The complicated part: For those who believe (the operative assumption here) that different cables have distinct sonic signatures that justify auditioning, switching, system matching, and the sometimes surreal cost of some cables compared to standard cheapo rca's, it seems quite likely that different cables will sound one way or another initially. How can you say what you're listening for generically, without reference to a particular cable in a particular set-up (including room)? Do all cables have the same sonic limitations when new? Do they all change at the same rate and in the same way? I don't see how any empirical "proof" could be generated with the extraordinary number of variables that would be present, and this is without the input of cable and break in doubters who will surely step up to the plate.

The easy part: Set it and forget it until some break in mile marker is reached. Establish some sort of input to output set up that can be run non-stop and check it at some time interval that seems acceptable to you. Check it periodically to see how it sounds to you. Ignore it most of the time until it goes into its place in the system or is returned.

I described making a break-in thingy for a phono cable that had a right angle din plug using a tuner and pre-amp in another post on Audiogon. I made this because a protracted break in was claimed for the cable, and I didn't want to go through several hundred album sides deciding if I wanted to keep the cable. Perhaps it made a difference; perhaps I might have heard it and noted it at LP side 1 vs. side 50 vs. side 143, but listening for such nuance in break in just wasn't a worthwhile activity for me.

What listening for in break in over various time intervals might be worth to the original poster or anyone else is up to them. You might or might not be able to hear a difference. If it is of interest to you, fine. I certainly know that it's not worth anything to some.

Rouvin, thank you for the thoughtful answer. Honestly, I don't think cable burn in is anything other than each listener's own perception. If someone hears a change in their cables after their hard fought burn in, that's fine with me. If another calls it bunk, that's fine with me also. It would take a lot more time and effort than I'm willing to put into it to find out for myself. My system sounds fine to me. There's no inclination for me to listen critically enough to hear the "sonic signature" of my interconnects.

Timrhu said it all. If you take the time and it is of interest to you one will conclude that cables do change with burn in. If it seems like a waste of time and you dont care, then that is fine and I completely understand why one thinks cable burn is all in the mind.

I would not say every cable sounded better in my system after burn in. It depends on the system and your sound preference. Some cables may change to the point they upset the balance one likes in a system. System is now to bright, not enough bass etc... My only point is they change and give a new cable a little time before deciding it's not for you.

I have heard some engineers or technicians say that wire is actually a capacitor so that in itself would cause some change. Now whether the wire (tail) is wagging the component (dog) or vice versa, I don't know? So in effect evertime you change out a wire you are changing the capacitance between two components? Even if a component is warmed up say after 2 hrs. and then you switch wire you are supposed to give it a few minutes to settle in. Some wire has better immunity to RF and therefore has a blacker backround right out of the box.

I must admit I am at a loss on how all of us cant agree on this one. Every cable I have owned changed over some burn in time with a system. I have owned many, many cables over the years.