Fig. 6 Harmonical proportions according to Pythagoras and Aristoxenus. Pythagoras divides the string length into 9 parts, in order to calculate an harmonical proportions shown in the figure. Aristoxenus, to achieve the same result, divides it into 15 parts.

Fig. 7 Division of a monochord puris numeris from Ludovico Foliano, Mvsica Theorica, Venezia 1529. C-d1 - 10/9; C- d2 - 9/8; C-E - 5/4; C-F 4/3; C-G 3/2; C-A 5/3; C-Bb1 16/9; C-Bb2 9/5; C-B 15/8; C-c 2/1