Headphones - Wikipedia, the free encyclopedia
1 History 2 Applications 3 Electrical characteristics 3.1 Impedance 3.2 Sensitivity 4 Types 4.1 Circumaural 4.2 Supra-aural 4.3 Open or closed back 4.4 Ear-fitting headphones 4.4.1 Earphones 4.4.2 In-ear headphones 4.5 Headset 4.5.1 Telephone headsets 5 A...