Most people here seem to own HD800's numbered above 10,000 and claim there is no difference. A few folks who own very early models say there is a difference between the early ones and the ones that come above 10,000. So I suspect there was a revision somewhere along the way.
My HD800 is serial 9xxxx, and since it's somewhere in between, I have no idea whether mine predates the revision or came after it. It's quite frustrating as I don't have another HD800 to compare to see whether I should sell off my HD800 and buy a relatively newer one, if the "revised" HD800 indeed sounds better overall as people who have heard the difference claim so.
If anyone's compared HD800's in the 8-9000-ish and 10,000+, could you please tell me if my 9xxx HD800 should sound just as the same as the later series, or that a revision took place after my HD800 and that I would benefit by replacing my HD800 with a higher number unit?