This is how I feel about the HD650s, but people seem to love them because of this quality. One man's monolithic and shallow, is another man's smooth and sweet. To me the Z7 is somewhere between. The bass definitely makes itself present for an overall darker sound, but the Z7 has a crisper upper end than the Senns which brings out more detail.
To me these are like the Denon Dx000 series perfected. The bass is similar to the Denons, but tamer. They cover the entire lower end very well, but it isn't as visceral. Specifically love the way they bring out kicks and subtle bass lines. But listening to
Mala's "Changes" for example, the sub bass is definitely there, but not with the same dominance as my Denons. Which may be a good or bad thing. My main problem with the Denons though were the sharp highs. The Z7s fix that. Really loving these for more modern synthy, bassy, dance type music. Stuff like
Shed,
Sd Laika, or even
Mount Kimbie kill with these. If I want to listen to more natural vocals like some old Lauryn Hill though, probably pick up the MA900s instead. There's just something about the MA900s that allows you to hear these subtle melodies you've hardly noticed before. Shouldn't have expected closed cans to sound like my favorite open headphones. But as far as closed goes, the Z7s have one of the best soundstage I've ever heard. And haven't heard the Fostex yet, but these dethrone the Denons as my favorite basshead headphones out there.
Also noticed that these are pretty sensitive to ear placement like the MA900s, which could be why everyone has a different opinion on them.
In the end though, I bought these because I thought they would be a bassier, closed MA900, but instead I got headphones that are everything I wanted my old Denons to be. So I guess I could finally stop regretting I sold them.
Edit: And holy **** these are like the Rolls Royce of headphones. Every centimeter of these things are quality.