I'm not too familiar with the Sennheiser lineup, I'll admit. The HD600/HD650 always seemed like "mid-fi" offerings, though maybe that's only just now the case.
What I do know is that if they kept selling the Orpheus systems (which are apparently even more expensive now than they were brand new due to rarity and exclusivity), even the HD800 would just be "mid-fi" for the Sennheiser range right now.
No idea if the history is written down anywhere, but here's roughly how I understand it (to look at Sennheiser flagships):
HD 565 Ovation (sometime around 1989-1992) -> HD 580 Precision (sometime around 1992-1995) -> HD 580J, J is for "Jubilee Edition" (limited edition, I want to say 2000 or 2002), they're HD 600s by another name (and without the blue marble finish) -> HD 600 (roughly in-line with the 580J) -> HD 650 (like 2004)
The prices went from around $250 for the 565 to $299 for the 580 (and those were TOTL), $399 for the 600, and $499 for the 650. HD 800 came along around 2009 and absolutely re-defined "holy crap that's a lot of money for cans" - I'm thinking in response to some of the more exotic Grado models pushing up on that price-tag (GS-1000 in 2006 at $1k, for example; but with the Grados you have to remember labor/production is probably higher than it is for most any other manufacturer and they don't do huge volumes).
Beyer followed suit with the T1, replacing the DT880 as their "flagship" and more or less overnight Sennheiser and Beyerdynamic turned $300 headphones into "mid-fi" or "entry-level" when before they had been absolute top dogs (as far as dynamics were concerned, you had the DT880, K701, and HD 600 or 650 - sure there were still STAX systems and the O2 was still major bucks, and sure the ESP/950 still existed at $999, and sure the RS-1 was around, and sure JVC and AT and Ultrasone were making majorly expensive art cans, but I think it'd be safe to say all of those COMBINED don't approach the press or volume that Beyer or Senn enjoy individually (e.g. sure the Edition was like $3500, but they made less than 1000 of them)).
The HE series are a bit of an oddball, and I don't know where they exactly fit into the equation, time-wise. I know they were in that "exotics" class like the Ultrasone Editions and the ATH-Ws, they weren't pushing them mainstream. I think the HE60 was originally around $1k on it's own (but I don't know WHEN that was, I would guess mid 1990s though), and the HE90 system was supposed to be like $12,000-$13,000 BNIB, but iirc there's only 300 of them.
It's as if "fidelity" has come to mean "price tag" and not "actual sound reproduction performance" these days.
Yup, and of course if I can spend more than you, it means I'm superior to you, as a human being (and/or ape/dolphin using a computer).
I honestly blame the influence of the computer hardware industry and the massive popularity spike that headphones have received from Beats and Skullcandy pushing a lot of "techie" people into the fray. I'm not saying Beats even drove prices up; they entered the market on level terms competing with Bose and Sony and more or less ignoring anyone else. I see the massive price hike as manufacturer's trying to separate their products from "consumer-level" hardware, in order to satisfy the customers from above who need to feel special (and you can see this with computer hardware too - how much truly consumer level crap is branded "pro" these days?).
And yeah, I derailed my own thread. I don't care.
I hope I got all of the ones I missed, and I'll use this post as a marker for new suggestions so they get added.
