Body of 11 ribs: six of sycamore and five of rosewood, articulated by thin inlaid strings of ebony and an undetermined light-colored hardwood, possibly holly. The two-piece belly is of fine-grained spruce, the grain broadening slightly at the sides. A carved rosette of pearwood is set into the belly. The belly is reinforced by ribs running perpendicular to the grain. The neck is of ebony. The pegbox is veneered with ebony. The instrument is strung with 13 courses of strings: 11 on the main pegbox (9 double courses plus 2 chanterelles) and 2 on a second pegbox, which is glued to the bass side of the main pegbox. The lowest six courses on the main pegbox and the two courses on the second pegbox are tuned in octaves; the lower of each pair of strings is overspun. The tuning peg for the treblemost of the strings (chanterelle) is fitted in a carved dolphin's head glued to the treble side of the main pegbox. The hardwood bridge is veneered with ebony.

The theorbo-lute is a double-strung archlute with a single chanterelle and a second nut attached to the pegbox for one or two off-board drone strings. The body is smaller and the string length shorter as compared to the theorbo proper. The theorbo-lute was the instrument of the 17th-century French school of lutenists and persisted in use into the 18th century, when Bach and his friend the lutenist Sylvius Weiss wrote music for it.