Language lab

The language laboratory is an audio or audio-visual installation used as an aid in modern language teaching. They can be found, amongst other places, in schools, universities, and academies. Perhaps the first lab was at the University of Grenoble in 1908. In the 1950s up until the 1990s, they were tape-based systems using reel to reel or (latterly) cassette. Current installations are generally multimedia PCs. The original language labs are now very outdated. They allowed a teacher to listen to and manage student audio via a hard-wired analogue tape deck based systems with 'sound booths' in fixed locations.

The 'traditional' system generally comprises a master console (teacher position) which is electrically connected to a number of rows of student booths (US: carrels), typically containing a student tape recorder and headset with a boom arm microphone.

The teacher console is usually fitted with master playback source equipment (tape recorder), some means of monitoring of each booth in the class via the teacher headset and an intercom facility offering 2-way communication between teacher and student.

All but the most simple or first generation laboratories allow the teacher to remotely control the tape transport controls of the student booths (record, stop, rewind etc.) from the master desk. This allows for easy distribution of the master programme material, which is often copied at high speed onto the student positions for later use by the students at their own pace.

Better tape laboratories housed the tape machine behind a protective plate (leaving only a control panel accessible to the students) or locked the cassette door. This kept the expensive and sensitive decks free from student misuse and dust etc.

Once the master program had been transferred onto the student recorders, the teacher would then hand over control of the decks to the students. By pressing the record key in the booth, the student would simultaneously hear the playback of the program whilst being able to record his or her voice in the pauses, using the microphone. This is known as an audio active-comparative system. From a technological point of view, this overdubbing was made possible by use of a two-channel tape recorder

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