12-15-11: Transaudio
...
What DOES happen is changes in your ears day to day. Weather, humidity, your health, how tired you are, can play a huge role in sound "quality" (i.e. your personal perception of sound ). Also, your attitude makes a huge difference. If you want to hear a difference, you will. This is demonstrable. And Temperature of the drive unit DOES make a difference, especially when you are the edge of power compression, a result of heat inside the coil. So could the difference be that the speakers sound better after being on for an hour and heated up? This could 100% be true. It would also be true then that the speakers sound worse after being driven too hard (too hot) and you have to let the spear cool down for it to return to normal (I HAVE heard this many times). But was time the factor-no, it was heat.
...
Very essential additions to what is normally more exclusively confined around, in this case, the speakers themselves. The medium(atmospheric conditions) and ones mental and physical condition/attitude certainly plays a very central importance in the perception of sounds and music.
Also very interesting, and rarely touched upon, is your mention of the "temperature of the drive unit" and how that is a significant factor in getting the best(or worse) of the reproduction of music through the speakers; and further how this(heat) comes to you as the real importance as opposed to the factor of time(as a product of what supposedly "settles-in" the speakers mechanically and even electrically over a longer period of time, independently of temperature as such).
In my own setup I've noticed the very positive effect of "warming up" my speakers with fairly loud volumes(while I leave the livingroom in which they play), but not by any means insane levels for about an hour or so. The sound opens up tremendously after this "treatment," becoming more focused, clear, subjectively louder(at the same volume setting, of course), better resolved, and even more freed in the presentation. If for a longer period of time over the following evening the playback level has then been significantly lowered again, the effect of the warming-up slowly wears off to the more typical "stasis" of the sound quality. I don't know whether this is a factor more closely related to, and more pronounced with the type of speakers I own(though I guess not), being that they're more pro-style, semi-high sensitivity(94dB) in nature with a 12" Beyma studio bass/mid and a BMS compression driver fitted into a 12" conical OSWG waveguide.
However, what you believe to be exclusively linked to temperature(heat), a friend of mine has also linked to time as a more permanent effect in the driver, where he theorized the occasional and not least sufficient heating up of the voice coils can actually de-magnetize areas in their vicinity, and hereby make for a more optimal "environment" for the voice coils/magnets to operate in. He stressed the importance of the heating up of the voice coils to be of a certain magnitude - i.e. rather hot, but not so much as to endanger the drivers - which is required to have the desired effect into de-magnetizing. In other words: this is not a mechanical issue, but one that may not have been addressed by many speaker owners if they've played mostly at lower volumes where the voice coils are hardly heated up in any way significant. Moreover, this could actually worsen the issue where rather sensitive speakers are used.
In pro environments the speakers are most likely used at much higher volumes over longer periods of time compared to domestic milieus, and so speed-up the process of breaking-in the speakers, both mechanically and electrically, to an extend that could likely diminish the perceived effect of time as a break-in factor here.
