Cable Burn In

I have been a cable tester for about 15 years for a small manufacturer.  I've heard maybe 100 different cables, most never making it into production.  Before I test them, I burn them in for 24 hours, minimum.  I have found that a new pair of ICs versus a 24 hour used pair of ICs can sound very, very different.  

I've also tested Monster Cable 300s series years ago and found no appreciable difference after 100 hours burn in.  I found a slight difference using Belden low capacitance ICs.  Then again, I found that High Fidelity brand cables sound terrible on any system I've heard, generally, very expensive systems of $300,000 to $1 million.  I'd rather listen to Monster 300s than High Fidelity cables for musical enjoyment.

Since comparing newly manufactured audiophile cables to burned in cables is so obvious to me as well as to others, may I suggest that some or many professional based balanced cables do not have a significant burn in change in sound.  Note that so many great recordings were made using cheap professional cabling back in the 50s to 70s.  Could they have been better with more advanced design and metallurgy cabling?  I don't know.

When I purchased my SME IV arm in 1989, the dealer said listen for a while, then bring it back for modifications.  He shot closed cell insulation in the arm to remove the low mid/upper bass hump and installed Cardas phono cable with an RCA junction box.  It took about a month (100 hours) until I found great enjoyment using my new arm.  I am still using this arm in 2018.  

Honestly never bought into the cable burn-in thing. It's a piece of WIRE!! There's nothing to burn in................Try this, take two brand new identical cables. Keep one set aside and run the other set continuously in your system for a week, a month, however long you want, then have your wife or a buddy swap them back and forth, double blind, so that you have no idea which set is in the system or even if they swapped them around. I'd bet you good money that you can NOT reliably tell which is which or even if they've been swapped. You may guess right a few times, but I'd virtually guarantee that you can't honestly and repeatedly tell which one is in the system.......................Dude, it's WIRE.................45 years in electronics.........doesn't make me an expert, but I do understand a few things better than many hobbiests

Thank God we can't take this discussion or others like it to a "Game of Thrones" environment.  The carnage!!!!😮

I just recently bought quite a few brand new Audio Note cables interconnects and speaker cables.
I had borrowed the store demo cables prior to ordering and receiving my new cables. 
I replaced each demo cable with a new cable one at a time. Each new cable did not sound like the one I replaced. I asked the dealer about this. He said give each cable about 50 hours of music playing through them and they will start to bloom and sound like the demo pair.
Sure enough after 50 hours they started to bloom.
I experienced the same results with every other cable.

Spent 45 years working on top-shelf military electronics and have been an audiophile for just as long. I don't buy into the cables need to be burned in BS. It's a wire, it won't change tomorrow or next week or next year unless it breaks, shorts or opens. I honestly think that mega-cable vendors want you to hang in there until you essentially get used to their "wonder cable" and have time to talk yourself into believing that it just keeps getting better every day. ........All military grade gear gets "burned in".....usually at high temp, or alternating hot-cold cycles........to find out if it will fail under stress, that's it. The specs don't get better or worse with use..........if anything they get worse over time as components age............Wire doesn't "age", it's just wire.........If you don't believe me, pick up two identical sets of cable. Put one in your system and let it "burn in". Set the other aside during that time. Then have someone else swap back and forth between the burned in cable and the virgin set without you knowing which cable set has been installed or even if they changed anything at all. I'd bet good money that you will NOT be able to reliably and repeatedly tell which one is in the system..............You'll guess right some percentage of the time, law of averages, but you won't reliably be able to tell one from the other..............It's just wire my friend. If you don't like the way it sounds when you first hook it up, it won't sound better a month later, unless you talk yourself into believing it does.