This is conceptually the simplest ocarina tuning which makes each hole individually sound a fourth resulting in a hypnotic scale of an octave compass facilitating trills and glissando composition.
If they are made in A440 range they result in authentic pitches when fired.
Prolonged playing is known to produce a transcendental state.
They are mainly used by group music improvisors, speciality recording producers , individual musicians ,complimentary therapists,shamans and collectors.
Our version of this scale has the (optional) innovation of two extra holes for the thumbs each of which individually sounds the same interval produced by any two of the fourth-sounding finger-holes opened together-i.e. -a sharp fifth.
Interestingly,the extra holes extend the range to the optimum for ocarinas-an octave plus three notes.