Talk box

A talk box is an effects unit that allows a musician to modify the sound of a musical instrument by shaping the frequency content of the sound and applying these changes to their own voice. Typically, a talk box directs sound from the instrument (most commonly an electric guitar or keyboard) through a driver into a plastic tube. The musician puts the end of the tube into their mouth, and shapes the sound into words and phrases. The modified sound is then picked up by a microphone, amplified, and blended with the instrument's unprocessed signal to create the final effect.

The vocal articulation does not directly produce the sound; instead, the mouth acts as a filter that emphasizes and attenuates different frequencies generated by the instrument. This creates the illusion of the instrument "talking" or "singing" along with the musician.

The effect is achieved by using the human vocal tract (mouth, throat, and nasal passages) to impose speech-like patterns onto the instrument's audio signal. The player manipulates their mouth and tongue as if speaking or singing, but without actually vocalizing. This shapes the instrument's sound into recognizable, speech-like articulations. The clarity and intelligibility of the effect depend heavily on the musician's technique and articulation.

While often associated with funk and rock music from the 1970s and 1980s, the talk box continues to be used in various genres and by musicians experimenting with unique vocal effects.