A variant of the Lincoln Effect, which I have come to use extensively, is the Background Effect. Playing music in the background, while I work, in and out of the room and while assessing technical measurements, has an interesting effect. I play the next CD up, and I play it all day, and I take mental notes of tracks with particular effects or utility. My comment is on the different kind of evaluation of the speaker under test which is occurring in that mode. There is a global assessment of appeal or resistance, of feeling-states or level and kind of involvement, which, over time, associates with speaker component evaluation and selection. It seems unlikely that those observations would come to the surface via directed, focused, evaluative listening sessions. As sdecker says, we're too focused on the minutiae and technical to allow the global to penetrate.
This effect is similar to what many pros have mentioned. A new set of headphones or preamp, or mixer, etc. takes about two weeks to 'settle in'. They don't typically talk about equipment burn-in, but rather a form of psychological familiarity or knowing that allows a final accept/reject decision - to use or not to use for their technical art. I know that people on this thread have expressed this factor as their interpretation of what 'burn-in' is really about. There is truth there, along with truth of component maturation under stress.
Anyhow, this week I hope to compare first vs second order, both time-aligned in the 02. (while packing and preparing to move - what a trip.)
