Originally Posted by [DANGERDAN]
It all depends on the equipment my friend, some amplifiers have capacitors that change with time and can take days or even weeks before they are relaxed and produce their full potential. Not all do but some have this effect and the same goes for other audio equipment's that have this outcome.
Speakers also can change in sound, i had the chance to challenge myself and a friend into doing blind test's with two B&W 683 which both had different break in times. One was straight out of the box and the other was a floor model which had been used for quite a few months, we set the two on a switch and proceeded with some random comparisons with both of us testing each other so we were not vulnerable to cheating or incorrect testing.
We were quite enjoyable able to tell the difference and understand why, this is not the case for all speakers and it is so very dependent on the materials used from different variants of speaker technology and i think the b&w have the most complex of materials which is probably why it should be more noticeable.
Experience is very important in discovering what is true and what is not, if you have unbiased judgement and tend to not be affected by placebo then you probably have the best chance to test things accurately, people like to judge things based on technical research evidence and however much that is quite reliable there are things that cannot be tested or proven at least not with equipment. Physical changes in audio equipment can affect the sound output but show no changes in the signal when tested and these are one of the things that people don't sometimes grasp but engineers do understand why.
The differences you heard might
be due to break-in, but you don't know that for sure.
1. Even if you had them side-by-side, their different relative position in the room would be enough to affect their bass output, making "identical" speakers sound slightly different.
2. On top of that, the drivers and the components in the crossovers have tolerances (small variations from one unit to the next). It is possible the small differences in sound were from parts tolerance issues, not from breakin.
Edit to add this: As for the capacitors, you're likely referring to the big electrolytic caps in the amps power supply. They do have some "break in," but I seriously doubt it's audible. Those caps aren't even in the signal path.Edited by beaveav - 12/11/12 at 4:21pm