Tapping, 20th Century

Tapping techniques and solos on various stringed acoustic instruments such as the Banjo have been documented in early film, records, and performances throughout the early 20th century. The clavichord was an early acoustic keyboard instrument that used a mechanical hammer to "fret" a string for each key. It was followed by an amplified version, the Hohner Clavinet in 1968.

Source: Wikipedia > Tapping