Sits relatively tight and is clunky (but also in the long run not uncomfortable - just at the beginning a bit unusual). When switched off Active Noice Cancelling (ANC) hollow sound. Very effective active and passive noise suppression. When the ANC significantly better sound. I often fly and the HC800 is now my reliable, constant companion. Engine and conversation noises are largely hidden and I can look at soft music behind the clouds. Have been a few times on the plane picked up the HC800 to chat with the hostess and wondered that myself this crash has been so little disturbed. Battery lasts for weeks. CONCLUSION: All in all, nothing for hi-fi enthusiasts. The sound is (ANC) very good - but not great. As a travel companion in a noisy environment, I can only recommend HC800! Very good price / performance ratio!
