It was a stringed instrument with a wooden soundbox of semicircular form and wooden arms elastically connected to the extensions of the soundbox, allowing an imperceptible lateral motion thus creating a wave-like resonance.
Often, the soundbox had a concave crescent shape (like the phorminx) but could have sometimes been in the form of the letter “U” with three or four strings.Its cylindrical crossbar had balance weights and string tuning mechanisms. The strings started at the tailpiece and tied with loops onto knots of leather strips which were wrapped round the crossbar. The careful rotation of each leather bulge permitted the tuning of the string.