Quote Originally Posted by RobotCzar
I'm still not sure I understand what you experienced, but it seem you are saying that the first track you play sounds bad and then things get better? I am not sure what that has to do with burn in (or "run in") but it does indicate that electronics can go bad and effect the sound of what we end up hearing (I realize no one has ever claimed otherwise). It sounds to me that your player is simply defective, which is probably the case with any unsubtle audible changes in audio electronics. Do you see a connection with the problem you heard and the idea of burn-in or run-in?

I suppose it is necessary to make the point that, in my opinion, it is possible to have audible differences due to electronics. And, I don't know anybody who has ever claimed otherwise. The contention is that properly performing components (i.e., components that are performing within their spec AND have specs that are reasonable) do not have audible differences. I think there are plenty of components that make it past Q/A that have audible problems--these could contribute to the belief that there are major audible differences among electronic audio components.

I grant that a problem that only occurs on the first track played is strange. I have a CD player that consistently mistracks (briefly) after about playing for 5 minutes and then has no problem regardless of how long it is played. I assume it is defective, but the problem is too trivial to pay to fix (but is damned annoying).
Please don't rephrase what I said. I heard a difference from one track to the next. Nowhere did I say anything about the first track on a CD. The change was permanent. It sounded as if blankets had been removed from my speakers. Stop trying to read things other than what I said. To re-iterate: I have been an enthusiast since 1967. I have owned many varieties of speakers and electronics. I have scratch built amps and preamps and I have modified regular production gear. I am a BS EE and have some knowledge of circuits. The portable in question is a Technics. I would be the first to say that all properly functioning gear sounds alike. My lady friends may not agree with me on that. They seem to have a preference for tube gear. Some of you will attribute that to a roloff in the high end of tube gears frequency response. If that is so neither my ears nor my test gear can hear/measure it. Once again I will say "If I hadn't heard the dramatic change firsthand I would not have believed someone else reporting it". I think I'm going to build a better power supply than the wall wart and listen for any more differences.