The Octave Monochord is stringed two-sided, on one side with 20 overtone strings in c and 4 Tanpura strings (C, c, c, G)
Monochord with 22 overtone strings + 6 A + 6 strings
Monochord with 30 overtone strings is 26 c‘ + 2 c + 2 g strings.
The Pythagorean Monochord is suited to play pure overtone spheres and can be used to demonstrate principles of mathematics and harmonics by inserting bridges. Its is stringed single-sided with 25 blanc + 5 bass strings, tuning c / C.
Monochord with 19 overtone tuned