What is a high end stereo SUPPOSED to sound like?

Bryon, I too have noticed that effect. At times I've used it as a measure of whether I've really upgraded.

Same experience re slowing down - it sounds less like a mechanical reproduction and more like real instruments playing. Less forced or contrived- as a result, the perceived timing- the stuff 'in between the cracks' is more apparent. This is not 'resolution' or 'transparency' as often used in the audiophile sense, which often takes on a hyper-detailed quality, and is anything but musical.

Same here as well. I think that when we hear more of the music being played, we're simply taking in more info as there is more to the beginning and end of each note, making it seem longer when in fact the same amount of time passes but we absorb more, process more, appreciate more and since we are used to a particular piece of music, it begs comparison.

If one were to time a particular piece of music and then go back and add more instrumental playing, in the same time frame, I think it would have the same effect. We'd be processing more info, or in the case of hearing a recording better, that subtle effect would give the same results.

Or something like that.

All the best,
Nonoise

NoNoise- you hit upon another aspect of that perceived 'slowness': decay time. Many concentrate on the leading edge, when the back-end of the 'wave' is equally important (and doesn't make for stridency, either).

Ok, so I'm not crazy. Or at least my ears aren't crazy.

Interesting comments. I particularly like Nonoise and Whart's observation that realistic decays are at least as important as realistic attacks. In fact, I would add that to the list of answers to the OP's question...

One of the hallmarks of a high end system is that it can present decays convincingly.

Bryon