Stenomask

A stenomask is a hand-held microphone built into a padded, soundproof enclosure that fits over the speaker's mouth or nose. Some lightweight versions may be fitted with an elastic neck strap to hold them in place while freeing the user's hands for other tasks. The purpose of a stenomask is to allow a person to speak without being heard by other people, and to keep background noise away from the microphone. It's a microphone with the ability to filter out background noise.

A stenomask is useful for speech recognition applications, because it allows voice transcription in noisy environments. Perhaps more importantly, a stenomask silences the user's voice so that it does not interfere with the surrounding environment such as a court or a classroom. The user can verbally identify the speaker, indicate gestures and unspoken answers, and describe activities as they take place.