What are we listening for during break in?


Is it time for a reality check? A few days ago a post was started which asked a question concerning burn in of interconnect cables. The consensus of answers agreed that this was a necessary function with no opposing view. The recommendation that got me thinking was to install the ICs between cd player and preamp and use a test disc for 250 hours. My immediate reaction to that bit of advice was "give me a break." That is roughly equal to listening to 250 cds. Considering the amount of time I spend listening to music, it would take me six months to break in ICs.
I have experienced a sonic change after new speaker break in period so I'm not argueing break in doesn't occur. Whether a sonic difference occurs after ICs break in is another matter.
My question is, what are we listening for when we run our equipment for 250 hours just to break in an IC or modification? I don't mean why listen to music, I mean what sonic difference are we hearing? Is it better, worse, different, What the?
timrhu
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I recently bought MIT cables NEW and the box came with instructions and stating 2/2 rule: Which means 75% performance in 2 days and 100% in 2 weeks. I am currently going thru break-in at present. I have had new cables in my exsiting system and they sound completly different than when installed them new few years ago.

Certain signature sounds of newer cable IMHO are unfocussed images, perticularly center, both in terms of depth, L to R and height. Bass very weak in the beginning. Some ringinging at upper mids low highs. Highs also a little weak in first few days. BTW I am in my second week of burn in.
Charlie101, stay right here. Opposing views are necessary if learning is going to take place. I take no offense from your statement. And you comment about electrical engineers is probably true.
Rouvin, I forgot to ask, if you were using an lp 143 times to decide whether or not you hear a change in cables, wouldn't you think the sound of the lp would change more than the cable?
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Timrhu,
The # of LP sides, like 143, was a hypothetical, not the # of times I repeatedly played one side of an LP, which would, as you imply wear it (and me) out. One point I was making had to do with the utter futility of trying to listen for changes in a cable during break in, especially a phono cable. Is the 20th side sounding better than the 2nd? How do I really know with 2 different LP sides at least 18 Lp sides apart in time? I haven't enough time or interest to listen to how much or how a cable's sonics may (or may not) differ at various points before "fully" broken in. Still, I will go to the trouble of setting things up so there can be a "set and forget" break in. For the life of me, I can't imagine how manufacturers believing in cable break in, particularly extended ones, can justify marketing phono cables that aren't broken in before sale -- even more so with things like directionality warnings and rt angle DIN connnetors on one end. (Try to find an appropriate break in connector for this that allows RCA to RCA hookup. They don't exist, so you'll have to make one or have one made.) As much as I think the sound of reasonably well made LP's through a good system surpasses well made CD's on excellent CD players, LP's are a pain compared to CD's, even for someone who has collected and maintained them for over 40 years.