Device to automatically determine the accidents of the key of a scale and the notes of all the chords of a given tone (Machine-translation by Google Translate, not legally binding)

摘要

Device for automatically determining the accidents of the key of a scale and the notes of all the chords of a given tone, characterized in that said devices are constituted by means of two superposed discs, of different diameters, united in their center so as to be able pivoting one with respect to the other, comprising the major disk in its visible periphery the twelve music notes, seven natural and five altered, inscribed in their normal and regularly spaced order that define twelve sectors, in each of which are inscribed all the notes susceptible to entering the composition of all the chords of the corresponding note, the second disc comprising, in its periphery, references deviated proportionally to the succession of the tones and the semitones of the major and minor scales, and presenting groups of windows whose geometric position corresponds to a certain chord and in each of which are susceptible to appear r the notes of the aforementioned chord when said sales group is placed in coincidence with one of the peripheral notes of the major disk. (Machine-translation by Google Translate, not legally binding)