insert earphone

...An electroacoustic transducer that converts electrical signals into acoustic signals and sends sound directly to the ear for listening. There are two types: earplug-type, in which the unit is inserted into the ear canal, and head-mounted type, in which a band is worn over the head and the unit is placed on the ear. Recently, earplug-type earphones have come to be simply called earphones. Although the sound quality of earplug-type earphones is inferior to that of head-mounted types, they are small and lightweight, and are often used for listening to hearing aids and portable radios, and for simultaneous interpretation at international conferences.

*Some of the terminology that mentions "insert earphone" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

…電気信号を音響信号に変換し，耳へ直接に音を送り込んで聞く電気音響変換器で，ユニットを耳孔に挿入して使う耳栓型とバンドを頭にかけてユニットを耳にあてる載頭型とがある。最近は耳栓型イアホンinsert earphoneを単にイアホンと呼んでいる。耳栓型は載頭型に比べて音質は劣るが，小型軽便であるので，補聴器やポータブルラジオなどの受聴，国際会議場における同時通訳などに多く用いられる。…

※「insert earphone」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報