First up, just to answer everyone at once, yes, I have rushed to judgement, and in fact my opinion has somewhat ameliorated since then, but I deliberately didn't alter the original post (being in OZ my posts appear during the night for USA) because I wanted an honest first opinion to stand and because I thought it would stimulate discussion, as it has. Good.
The HE-500s are used, so I don't know what hours they have on them They're the newer type with silver lead and leather pads, so may not be too old, but I doubt they need burning in.
I wouldn't mind hearing the HE-500 with velour pads, but it may be a futile exercise for reasons I'll get to...
Dagothur, my "No, it won't" was to myself, not meant as a general statement that the HE-500 would not do for everyone. I should explain that I listen to orchestral/symphonic music exclusively, so things like transient response, detail and even bass slam are not as important to me as they might be to someone into more modern forms. My priority is evenness of response, orchestral timbre and generally low listener fatigue (which I must say is a feature of both phones here).
Rezolver, I'm not sure how you came up with your 16 hours, 2 minutes, but you give me too much credit. I certainly didn't listen to them for that long.
Anyway, now that I've sufficiently stirred the pot, let's get down to tin tacks. After further listening, as I say, my opinion has somewhat softened. I can now see the HE-500 having considerable appeal to modern music folk. They can even make orchestral music sound more exciting than the LCD-2 on occasion, and without too much cost. There's an odd nasally colouration that intrudes at times, and I was once or twice aware of a sort of nullity, a flat area in the upper midrange that robs some instruments (castanet, say) of bite and definition, but this was rare and probably helped with lack of listener fatigue on poor material. One oddity:
I find the LCD has a wider and broader soundstage. This was one area where I was expecting the HE-500 to excell, but I found it to have a sort of pinched quality that kept the sounstage from expanding. My ears maybe?
I could go into further detail on sound quality but as of right now my main beef with the HE-500 is comfort: I just don't find those earpads big enough, and the edges of my ears are getting pinched. The clamping is also rather extreme, though that may lessen (the LCD is much kinder, but I seem to recall that that clamped rather harder initially). To live with these I'd have to do something about comfort or sound quality would be irrelevant.
So to sum up, I'm going to provisionally apologise to all HE-500 fans for overly hasty judgement. I'll tuck my ears in and continue listening because I want to get a handle on these cans and give them a fair go. It's rare in any phone to have this much excitement and definition combined with such low listener fatigue, so they deserve credit for that at the very least. I do wish someone could come up with an ortho that wasn't quite so damn heavy though. God, my neck...