 In particular, the vibrational attitude was transformed by eliminating the lower skin, a decision which simplified the tuning of the instrument’s basic frequency (30 Hz) and reduced the excitation rise time in the upper modes.A synthetic membrane was applied with isotropic characteristics and high flexibility on which the previously described map was drawn, with colors that made the areas of performance more visible.The shell and the tensioning hoop were realized in steel and aluminium; in particular, the tensioning hoop was made stiffer while the height was reduced and the adhesion surface increased.