TALKBOX
Talk box
The box has connectors for the connection to the speaker output of an instrument amplifier and a connection to a normal instrument speaker. A foot-operated switch on the box directs the sound either to the talk box speaker or to the normal speaker. The switch is usually a push-on/push-off type. The other end of the tube is taped to the side of a microphone, extending enough to direct the reproduced sound in or near the performer's mouth.The above text is a snippet from Wikipedia: Talk box
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