A device used to impose vocal formants on other sounds, e.g., the "talking guitar" effect first popularized by guitarist Peter Frampton in the mid-1970s. The talkbox setup consists of a small amplifier whose loudspeaker is fitted with a plate that covers the speaker cone, and has a small hole in the middle. Connected to the tube is a plastic hose, the other end of which goes in the performer's mouth and emits the sound waves from the loudspeaker. The performer then shapes their mouth to impose vowel and consonant formants on the sound. The effect is similar to vocoding, although the mechanism is completely different (and not really electronic, except for the amplifier used).
A variation on this is the Sonovox, in which the performer applies a transducer to their throat; the transducer is driven by an amplifier and transmits the sound into the performer's larynx by direct conduction. The performer then shapes their mouth to produce formants, in the same manner as with the talk box. The Sonovox was popular in the 1960s for use by firms which produced station-ID announcements for popular-music radio stations. A small battery-powered transducer makes it possible for people who have lost the use of their vocal cords to speak (with a noticeable "robot voice") using the Sonovox method.