I received the KNS 8400 and they checked out great in my studio plugged into my Aphex HeadPod 454 headphone amp. They have a no nonsense forward sound and are extremely lightweight at 0.5lbs. They feel light on my head but there are no worries about them flying off no matter how much head banging occur. They fit perfectly because of a self-aligning yoke headband and the comfortable cushions covering the 40-mm closed-back, circum-aural drivers that feature Neodymium magnets.

I liked the detachable in-line volume fader control (included with the (KNS 8400 and optional with the KNS 6400) for in the studio when you and others are sharing the same headphone feed and you'd like it louder or softer than everyone else. I also liked the twist lock cable that cannot inadvertently come out. Although designed as a studio headphone, DJs will love the KNS phones because each driver freely rotates up to 90-degrees for one-ear cueing. But I think there should be a duplicate input socket on right driver--for left-handed DJs where a left side cable might get in the way.

I found them to go louder than is safe and produce a clear sound with low distortion at any volume level. I also noted that the 2.5m cable, ear and head cushions are field-replaceable.