Having not heard the 590 (I blew my chance at the Headroom meet, even though that was my "homework assignment" from bkelly
), I can't comment specifically on them, but I would like to hypothesize a little bit:
1. Headphone newbie goes to Headroom show, sees the 590's attached to a sign that sez, "man do these suck!", puts them on his head then decides that this must be the definition of headphones that suck. This sound, whatever its qualities, must be what is meant by "bad headphones". Besides, Headroom (well actually one set of ears-- Tyll's), who are THE experts on headphones are telling me they suck, ergo they suck. "The HD600 is better?" OK, their sound MUST be the definition of "good headphones". Newbie walks out with the HD600.
2. Experienced headphoner with his HD600s and expensive amp and aftermarket cable, picks up the 590 and immediately notices their increased treble response. Ouch! he thinks. This doesn't sound like my trusty HD600s that I know like the back of my hand, it can't be *right*, and after all, if the HD600 is known for only one thing, it's that it's sound is *right*, right? Well that's what so many people at Head-Fi believe, and that's why I invested a lot of my hard-earned money in them. I'm not a chump am I? Experienced headphoner walks away, secure in the knowledge that his 600s are better.
3. People "complain" that the CD3K is "too bright". Well, I say that the HD600 is too "dim and woolly". Perhaps the reactions to these phones treble is simply due to the fact that so many ears have become accustomed to listening to the rolled off wooly HD600. Anything else sounds too "bright" in comparison, causing a knee-jerk reaction against them. Now, in my review of the CD3K, I freely admitted that the treble *approaches* a level where it could become bothersome to some listeners (but a good tube amp like the ZOTL sure helps). That indeed is that phone's primary flaw. Nothing at that price is flawless, certainly not the HD600 or HD590.
Now I'm not saying that anyone who likes the HD600 is "wrong", or even subject to any of the scenarios above. I simply pose some hypotheticals to think about.
bkelly is a very recent convert to headphones. I am somewhat responsible for encouraging him to dive into our world, which he has done with gusto. He had no history here on the boards, had never read the endless debates about this or that phone, and went to the Headroom tour with almost no pre-conceptions.
He walked out with a pair of HD590s. I suspect this is an under-respected phone around here, though again I have not heard them myself. Obviously Sennheiser intended them to be a replacement for the 580 (if not the 600), so they must think highly of it. Did they really "goof" with its creation, or is it in fact an advance over the HD580/600 with better, more extended frequency response? Have their ears deteriorated since they first designed the 580/600? Well, it's possible, but....
markl