Yeah, it's definitely a hit or miss kind of thing with people I find. There are many people who cannot stand that 2khz bump/ringing and thinner bass, and I can definitely see why. It's the same reason why lot of people can't get on with the lower end Stax I find as far as frequency response is concerned (lot of their lower ranges has that similar 2k bump, just not to the same degree with less ringing, but it can still make certain tracks "shouty". And the bass of course typically drops off a cliff on the low end Stax).
Worthy to mention is that he may want to try the Q701 first as they do have slight bit more of a meaty sound to them, it would undoubtedly be easier to get adjusted to. I found them to fill in parts of the midrange and bass a bit better than the K701/2's. It has less of a risk factor IMO. I see the K701/2's as more of a niche headphone really, so there's going to be somewhat higher risk involved than average that one may not like it. but I do happen to be part of that niche... I quite like it even after having/trying many higher end headphones, which is why I got them (well, the K702's) again
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