this is a great overview and interview with one of the people who worked on these new headphones.
there is also a frequency response comparison to the HD600.
spiler: looks like they are have some bass
i never liked the HD650, they were sounding very boring to me with no sub bass.
but because they are very comfortable, i will give the 490 pro a try.
Thanks for sharing, these are the points I found most interesting from the video:
On HD600 and 650:
"...when you take a look at the hd600 and 650, which are products that are commonly used among the professional users, people really love the audio response of those products but when you ask them 'hey what do you expect from a product?' they say 'I want a really neutral flat acoustic response.' But in difference to the hd600 and 650, t
hey [HD600 and 650] are not let's say the most neutral as it can get, so it's one thing that they say they want and it's another thing that they go for."
"I would not 100% agree to that [the HD490 having significantly more bottom end] even though on the frequency chart it looks like that. I would say that the HD600 is a headphone that was designed for audiophiles and also audiophiles like to listen into the details. And HD600 is also a product that is vastly used among the professionals so it also has a really good point in working with the details of the mix. But we've seen that there are also some points where you can like improve when you want to judge the details on
the lower end of the frequency spectrum."
Odd that he says this when the better bass extension seems to be the major improvement. Not sure it's entirely true that the HD600 was designed for audiophiles?
"What I really like about the the HD 490 Pro [compared with HD600 and HD650] on the top end is that I can really hear the details of different instruments played placed next to each other so for me it was very easy to identify what I've done and what I want or if the work that I'm doing is really up to what my idea of it was. And this is way more easy with the HD 490 Pros than it was with different headphones."
On measurements:
"We're measuring on a Bruel [and Kjaer] head and [for the] first time ever we will also share the testing and the frequency response curve that we did with those testings."
This is not entirely true: Sennheiser has shared frequency response curves in the past.
"I would recommend not to put too much interpretation into the curves. This is also the reason why we really hesitated to publish them in the past, because we somehow fear a little bit that people will take them as the only reference and we really want the people to listen to the product and then make their their judgment on their own."
On Harman headphone research:
"No, that's not irrelevant at all. It [the Harman research] has been part of the journey that we've been through in part of the acoustic design but we think that the best approach that we did is take that also as part of the overall thing that we are judging and not going with a theory and just following a theory. So yes we considered that it was part of the overall design but it was not the only principle that we followed."