Equipment Break-in: Fact or Fiction

Never thought much about it until I experienced it for the first time. Uncanny. A bit like cooking. You suddenly know when the soup is exactly the right temperature and all the seasoning blends into something surprisingly tasty.

This is a fact. Have you ever looked at an older circuit board? The flow of electricity changes the board. I have installed many cameras that had perfect focus and have returned two weeks later to find them out of focus. Gremlins perhaps! The question is: How much does the sound actually change? Does the tone change from harsh to smooth? Does the bass change from thin to deep? Does the soundstage come into focus? If I had to guess, from my own experience, it is 5 to 10 percent at the most.
Tim

I feel so badly that so many remain so naive. I guess some people will simply never know the truth, or simply refuse to except it. I does surprise me that people so ill informed would chose to take such passionate positions on things they obviously know little about.

If your wondering my thoughts on this topic, than you have no idea who I am, and maybe it's time to investigate.

Sos, excellant post

Just out of the curiosity.. how would you apply the "Social psychological phenomenon called positive test bias" to explain the difference between hearing "no (or less) detail" before burning in and "much more detail" after burning in?

I bet that psychological phenomenon cannot make you hear more things unless you drink too much!!!

Just my 2 cents.

Ake

Ok, since many of the "believers" seem to want to lambast us skeptics here is my reason for being skeptical, or at least attributing the bulk of the effect to the brain of the listener.
I have two systems, one in England (now in my parents' living room) one in the US where I have been "temporarily" living for 5 years. When I visit the UK, roughly every 18 months, for the first day or two my old system sounds bass heavy and lacking in detail. After a few days it sounds thoroughly enjoyable. When I return to the US my US system sounds detailed, but lacking in rhythm. After a few days my US system sounds very enjoyable.
Both systems cost about $3k, and a mix of new and used. I believe both are at comparable performance levels, and both represent pretty much the pinnacle of a $3k system. However both have different strengths and weaknesses. The US system excels at chamber music and light jazz. The UK system excels at rock, particularly live rock, but handles classical very well.
I believe that over a period of time, measuring days, my brain becomes attuned to a particular tonal balance. Since both systems don't contain a single component less than 5 years old (some are >10 yrs) burn in is not possible. Both are left permanently switched on.
Since I'm an open-minded EE I'm prepared to accept that there might be minor changes in sound over time due to many different second-order effects. However I also believe that these changes are swamped by the adjustment of ones brain to a new tonal balance, based on the experience I have just outlined above.
I also believe that to strive for the "perfect system" is something of a wild-goose chase, since I have found that I can live very happily with many different systems, provided that I have time to attune to their particular sound, and provided that they are reasonably good systems to begin with.
Hey, don't flame me ... I offer a sincere opinion, with evidence upon which it is based !