You mention bassy headphones and you put DT990 in the same league as DT770? I thought DT990 is an open can which means theoritically it should not be as bassy as DT770.
I have a Panasonic HTF-600 and Alesandro MS1. I can hardly hear great difference between the 2 besides that HTF-600 has more bass and MS1 sounds crisper in high and mid.
DT990 wasn't short of bass. You can do a side by side comparison at Jeben. I actually find the quality of bass and overall sq slightly better in 990 then 770. 990 open design give a wider sound stage which i certainly enjoy in gaming and movies. The impression of 770 being more bassy are likely due to the close design i guess.
Then again, open HP leak sound both way...making it only ideal in quiet environment. Even at home, i only use it late at night when everybody is asleep.
I have not heard those hp you listed so i can only compare with my Beyer (brighter) and Sennheiser (darker).
Say for instance, sound of 2 sword clashing against each other. In reality, the sound should be a high pitch and sharp "clank". Beyer sound more "correct" then Sennheiser. But such sharp sound can be quite fatigue to my ear after a while.
Sennheiser on the other hand sounded more mellow (dark). Pleasant to the ear but doesn't sound that realistic.
So...between realistic and comfort...i had to choose 1.
No, it wasn't a night and day difference...but I get to realized such difference the more I listened to them.