telephone earphone

7.105  telephone earphone. Earphone designed for use in a telephone...

circumaural earphone

7.103  circumaural earphone. Earphone having a cavity large enough to cover the region of the head including and surrounding the...

horn throat

7.102  horn throat. End of a horn where the cross-sectional area is...

horn mouth

7.101  horn mouth. End of a horn where the cross-sectional area is...