"Burn in" Are you serious?

Sorry, guys, but the laws of nature apply to "somewhat experienced audiophiles" just as much as they do to everyone else. It is quite common to hear changes in the sound of an audio system over time. But there is no way for you to know whether that perceived change is the result of a change in the sound of the system or a change in your perception of the system. (Unless you simply assume, contrary to all scientific evidence, that your memory for sound is perfect--but that's not knowing, that's believing.)

I had the oppertunity to compare a brand new pre amp with the stores demo pre amp in my home. Although both were the same brand and make preamp there was a huge difference. The one that was broken in was more open and a lot smoother.

I think perfectimage just answered the question quite perfectly.

Hi Jostler; It took me several years to acquire "critical listening skills", and using these skills is quite a bit different than listening for pleasure IMO. Perhaps you haven't expended the time and effort necessary to learn these, but many audiophiles have. If you are going to quote scientific evidence to support your position, then please do so. So far you've just stated opinions (even about the "scientific evidence")-- like the rest of us. I would think that someone reading/participating on this site would either have a different opinion on this issue, or more specific evidence for their "contrarian" view. No? Cheers. Craig.

Relativism: a theory that knowledge is relative to the limited nature of the mind and the conditions of knowing and hence not true to the nature of independent reality and that holds that absolutely true knowledge is impossible because of the limitations and variability of sense perceptions or that reality as it is in itself can not be known by minds whose modes of thinking and perceptions are essentially subjective or that thinking and perceptions sees relations of one thing to another only and not the intrinsic nature of an object and hence are merely symbolic.