Oh, it's not my word that they're bright, it's objective measurements and anecdotes from many consumers that they're bright. I'm not saying that you shouldn't like them, in fact I'm glad that you own headphones that you enjoy. I know from experience that the frequency response chart shows the DT990 would give me treble fatigue, and anyone who's sensitive to treble should do some reading up before buying them. Also , if the JBLs you recommend sound similar to the DT990, the OP ought to think hard before buying them if he's treble sensitive.
I can't say I'd recommend those Chinese headphones I bought. I changed my order at the last second and bought the ZS3. Fit is really good, they seem well built, and the sound is pretty good (balanced, detailed, solid bass, not too bright)... with one big exception that I can't get past. The bass sounds like it's centered right in the middle of my skull. I can see why people rate them highly, and for fifteen bucks they're pretty nice, but the bass thing makes them sound weird.
Edit: maybe I'm not getting a good seal on these headphones. When fiddling with the placement I get better results with the bass. I hate silicone tips, but that's all I have for them right now, so I'll reserve judgment until I have some comply foam that fit.
Techno sounds way better than goa trance. Listening to Kangding Ray - Hyper Opal Mantis and it's sounding very very nice for $15! I'm starting to see where the good reviews are coming from.