Octaves
The musical notes of the octave harmonics are produced by the simultaneous vibration of two tuned reeds with “octave interval”, ie a bass reed and a sharp reed with a just tuning.
These harmonics are also used mainly for folk and folk music, producing a powerful, full sound with no tremolo. The double models are the conjunction of two harmonics constituting a single instrument with two tunings in different tonality with a fifth interval.