Component Break In. Truth or Fantasy

I recently bought a pair of speakers that had a recommended break-in period of 200 hours, although at 197 hours they sounded pretty damn good...they also sounded pretty damn good before any break-in, so there's that. I then (last week) added (again, recommended by mfgr.) a fancy capacitor to the crossover that also claims to need 200 hours although a consensus among cognoscenti claims 100 ought to do it. Note that if you prefer the sound of the non broken-in component you are bound to dwell in a netherworld of certain uncertainty. Also worth noting are break-in time recommendations exceeding initial warranty/return policies...Morrow cables claim to require 400 hours. 

Truth for me. Especially with speakers.

So way back around 1977, I was a young man living in a mobile home with three other guys, up in Northern Alberta.  I didn't have a stereo and I didn't have any money to buy one.  But I had a used cassette deck from someone's car, and a couple of very cheap 6 inch speakers.  Again, out of a car door.  Just for a lark, I mounted those speakers in a couple of 8 cube cardboard boxes (that's 24" x 24" x 24" for those who have never moved a house).  Used basic lamp cord as speaker wire.  Not surprisingly, the sound was not very good.  But here's the thing.  After a couple of weeks, we were so accustomed to the sound, we all thought the "system" actually sounded pretty damn good.  So did the lamp cord "burn in"?  Did the speakers "open up"?  Did the cardboard boxes go through a molecular transformation?  Or did our brains simply become accustomed to the sound that was now perceived as being more than adequate.  This is absolutely a 100% true story, and IMHO, speaks volumes on the subject of equipment break-in.

Why is it that when things are supposedly broken in they always sound better? The odds of that happening are basically nil, yet we read about it all the time despite no objective evidence that it's real. The faithful (emphasis on faith) will go on and on about it, but it ain't happening.

Besides, manufacturers "voice" their equipment to sound a certain way so if it changed after x number os hours of use, that would make no sense and not be what the designer wanted. 

Read this post at an opportune time having connected a brand new streamer dac  two days ago. It’s a Lumin D3 and it has been running continuously since. First impression was that the sound was exaggerated on the high end, harsh and just bad. Right now I am streaming Katy Lied through Roon and Quboz and it sounds much better…fuller and more analog round but still not as nice as the D2 it replaced. Hope to hell it keeps getting better.