KNS 8400 : KRK KNS 8400 are good and reliable headphones.

"+" High quality product, perfect details in panorama, mids, highs, comfortable and for a good price. Good acoustic insulation.

"-" Some of the guys tested these headphones and found them very hot after wearing for a some time. But I think this is a usual thing for a closed type headphones. Low end is very flat or ... I have to compare with other monitoring headphones.

Update 2021: I love these headphones and they've been serving me well for 8 years now. I got used to them in the means of comfort and frequency response curve. I love to use them for surgical jobs, because of their precision that allows me to focus on tiny details that I might miss when using speakers (i do mix and monitor with them as well). I have not been using them everyday in a busy studio, but they had their duty for these years. Well, I wish it would stay like that for a longer time, but I must inform that now I have to replace the ears and headband cushions. But 8 years guys. I could not find original replacement and also read they are at a biting price so the parcel from China is on the way and my hope they will work the same.

Conclusion:

Cushions is the only issue I had over the period of use. Connectors and wire etc - all is good. But I also used headphones with care.

Yes the bass is moderate. But it is there.