break-in--bane or boon ??


as a reviewer , i often receive equipment which is new and has no playing time.

i have to decide whether to break in the component and if so, how many hours is necessary.

i have often asked manufacturers for guidance.

one cable manufacturer said the cables--digital, analog and power, required no break in. another said 24 hours.

when i reviewed a mcintosh tube preamp, i was told by a technician that no break in was necessary. all i needed to do was leave the preamp on for one hour in order that the tubes were "warmed up"

can someone provide an objective explanation as to the basis for break-in and how to determine how long to break in different components ?

for example, cables comprised of different metals, if they require break in, is there a difference in the requisite time for a given metal, e.g., gold, silver or copper ?

can someone provide an explanation as to what is happening during the break-in process ?

can one devise a mathematical equation to quantify break-in hours, as a function of the parts in a component ?
mrtennis
After assuming for many, many years that there must be somebody somewhere who indeed had all the answers when it came to just what exactly was happening with break-in (which I believe to be a very real phenomenom - just as I believe accomodation of hearing is quite real too), in the end I gave up as it became evident by default that no such person seems to exist, or ever has...maybe some physicist locked away in a lab somewhere knows the answers, but a recognizable source within the audiophile community doesn't seem to exist and I suspect it's because these things may, in complete totality at least, simply be unknown. IME there seem to be a few patterns that recur: that copper speaker wires usually take a good week or 2 to (fully) break in, that silver IC's often take somewhere around 400hrs (or even more) and that many manufacturers don't seem to want to be caught acknowledging that it exists to their customers. Maybe in the belief that it may either confuse them or that it may possibly discourage sales...or perhaps to avoid being in (what they take to be) the embarassing position of effectively having to admit to their prospective buyers that there's an aspect of their product's behavior that they themselves cannot properly explain...

My own experiences with a FryBaby that I've had for years strongly suggests to me that, with wiring anyway, insulation is likely the biggest factor (by far) that determines break in. But, you can look at the review I wrote up for that in the Agon reviews section.
Ivan. What you said may be true in a highly resolving system but not in mine. What makes the difference in my system is speaker placement. Stands, mass loading etc. But to be fair this is what I wanted and is why I have what I have. I do agree with the silver/copper but have never noticed any break in. However I'm not really an aidiophile but more a practitioner of music.
Donjr, don't get me wrong, your comments are entirely welcome. My system (and I've not yet been in a position just yet to finally post it on Agon and let everybody know what I'm working from) is a somewhat minimal CD-only, ss rig that cost less than $5k, with a little over a grand of power conditioning thrown in (which does do a pretty good job of helping with the resolution, I must admit). But, honestly I would never expect a fellow Agoner to apologize for their rig, no matter how humble! That's one of two faux pas at this point in my hobby I try to avoid: 1) expecting someone else to apologize for what little they have and, on the flip side, 2) complaining that I don't have enough money to afford what I want ;) Either one of those thing is bad form to me. But, so many of us, including myself, have had very humble beginnings in this hobby and I see no reason to forget that. I also expect myself to extend that sense of courtesy to others who've had different experiences than my own - even if it is with the same gear as I use. If someone is talking about their direct experience then they're talking about their direct experience. That's all the authority anyone needs. What I was trying to do in my post above was talk about my own experience, in no way did I mean that to be taking pot shots at you, or your system, I apologize if I made it seem as though I were.
Roy, you've certainly been around a lot of components. What does your own experience suggest?
hi joe:

well there is the placebo affect.

what is so confusing is the difference of opinion among manufacturers.

i have found some cables do require break-in. i experienced this when i connected a pair of interconnects between a cd source and a receiver for 300 hours. then i reviewed the cable. i still had the cable in the system and three days later the stereo system sounded different. it could have been that the cable was not fully broken in.

there is only one way to be sure.

keep listening to the stereo system which has the componemt under consideration until the stereo system does not change its sound.

it's disconcerting when cable designers say that a cable doesn't break in but rather yours ears acclimate to the cable.

so the conclusion is that there is a variation in advice from manufacturers and there is no rule of thumb. i guess just wing it.

so i allow 300 hours, as a standard practice.