Echo Room

Japanese: エコールーム - えこーるーむ

...In recording, broadcasting, and concert halls, this device is used to give music a richer sound, to depict a dramatic scene, and for psychological effects. Currently used echo devices include echo rooms, iron plate reverberation devices, and various types that use time delay devices. An echo room is a room whose interior is treated with materials such as concrete or tiles that reflect sound well, and has a long reverberation time. ...

From [Reverberation Room]

...For the measurement of sound absorption rate and sound insulation characteristics, standards for reverberation rooms are set by JIS or international standards (ISO). In addition, reverberation rooms used to artificially add reverberation to songs and music in the production of record programs are generally called echo rooms. Echo device [Shoji Yamamoto]. ...

*Some of the terminology that refers to "echo room" is listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

Japanese:

…録音や放送，ホールの演奏などで，この装置は音楽に豊かな響きをつけたり，ドラマの情景描写や心理的効果のために用いられる。現在使用されているエコー装置には，エコールームや鉄板式残響付加装置と時間遅延装置を利用した諸方式がある。エコールームとは音がよく反射するコンクリートやタイルのような材料で内装を処理した部屋のことで残響が長い。…