Ooh, I must have hit a nerve.
Well, you did kinda hurt my feelings. Questioning someone's integrity and history will do that. Especially when it's done on the esteemed behalf of inanimate objects.
Google Professor Brian Cox's statement on opinions
Isn't Brian Cox a physicist? I don't see how his opinion on opinions is any way relevant. Would you trust a linguist on math? You don't trust a sound engineer on sound engineering, that's for sure.
Citations for sales figures please? You're talking about the treble on the M50x as if the M40x doesn't have the same problem... you can't be serious?
Sales figures? Pffft this is the internet. There's over 5000 reviews on Amazon for the 50's and under 2000 for the 40's. I barely care enough to look any further than that.
As for reviews... you and I must be looking in different places, the forums are awash with people saying the M40x are better, especially quoting "less bass" which the measurements seem to disagree with. I can only assume people who don't know better are confusing the better bass quality with 'more' as it's closer to the kind of sound you get in a high-end planar.
We are looking at different places. Again, I looked at the amount of reviews on Amazon and to be honest, I didn't even have to check. So unless the most used consumerist retail source in the Western World has more audiophiles reviewing products on it's platform that it does non-audiophile consumers, it surely qualifies as a good gauge of mainstream popularity for a product.
Don't take this personally, but if I had a quid for every "qualified" sound engineer I know I could probably buy another M40x
I don't take it personally. This is the internet. If I took things personally here, I'd have had to attend therapy after playing any competitive multiplayer game. Obviously, I can see where you're coming from with regard to overblown claims on the web. Rest assured, however, I indeed attended Cape Audio College in 2006 and subsequently made a living producing music before studying copywriting in 2008. Yes, my life story is just as silly as it sounds and if I had a quid for the amount of times people questioned it, I'd be able to study something else... Maybe opinions on opinions from physics professors.
I feel like these two paragraphs deserve no comment, a lot of it's irrelevant, kinda derails your own argument, and also appeals to you as (questionable) authority on the subject, which is a logical fallacy anyway. Never mind buying into marketing copy.
Whoa Nelly! I guess my paragraphs did deserve comment because that's what you did!
Anyway, my authority on this subject may be questionable, but snark can't change my academic past so what does that make your authority? Dubious, at best? Likely nonexistant aside from being able to afford a pair of Audeze? I don't know and I don't care. That you don't believe in my substantiation doesn't change the fact it is at least a substantiation. That you haven't substantiated bugger all but some measurements from the internet (which I don't believe in anyway. Check my sig.). And then you accuse me of taking too much from the same place?? Logical fallacy indeed.
Since you've brought up your Fostex, I might mention that I also own the HD600 and LCD-2, objectively arguable as much better references of both neutrality and low THD respectively.
WOW! Those are great cans. Did you have the opportunity to blind demo both before you bought them? Or did you have an idea that you were going to buy them before you tried them -- like maybe read something off the internet? I suspect it's kind of half and half? I'm just saying that you own 3 of the most loved pairs of headphones on Headfi and basically the entire internet... Anyway, how does a 2006 pair of T40's compare to what you've got there? T40's cost around R800 back then so I'm not bragging or anything -- quite the opposite. I own planars and HD6-- Sennheisers as well. I wouldn't track on those headphones because when you mix you're constantly removing your headphones and checking on monitors so you kind of want something that's ok with being chucked around.
That aside, I still use the T40's for that purpose to this day -- although these I got for R250 from Gear Junkies.
I own the M40x and listen to it every day and the great thing about objectivity is it doesn't actually care who wants to be right.
That's great. They are very good headphones. I prefer my Z55's but I do like the M40X's and still maintain that they wipe the floor the M50X. You are right about objectivity, but one can't attempt to condescend and discredit another person objectively, can one? You literally have no idea who I am and yet still made some harsh assumptions about me because... I had a different opinion to you!
EDIT: One more thing I'd like to know, have you actually compared the two back-to-back?
You seem to be basing a lot of you opinions on words written on the internet.
I demoed both of them at Mars Music, Heathfield in 2016. I liked the M50x's as Killer Mike did sound amazing on them, but I also felt that the M40's were more what I was after.
In the end I bought DT990's. The spikiest things ever but so, so fun!

@Arie: I hope you're enjoying the show buddy!
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CLOSING THOUGHT: I don't enjoy getting into arguments on the internet. Especially not on forums and especially not on other people's threads so I must apologise. I will try my best not to share anything too controversial in the future.