The Probert Encyclopaedia of Music

THEORBO

A theorbo was a musical instrument of the 17th century made like large lute, but having two necks, with two sets of pegs, the lower set holding the strings governed by frets, while to the upper set were attached the long bass strings used as open notes. A larger form of theorbo was also called the archlute, and was used chiefly, if not only, as an accompaniment to the voice.
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