The Artademic design of Ranjer instruments allows six-note major and minor chords to be played by a novice, using only one finger. Here's how that works: In ancient times, fret placements were calculated by inverting the fractions and multiplying the length of the string, according to the saying, "As Above, So Below, But Vice-Versa.”
The three notes of any major chord are in the ratio of 4 : 5 : 6. So, if a string is 25 inches long, tuned to 440 cycles per second (A), the interval is 110 and the next note in the chord is 550 cps (C#), a ratio of 5/4. The fret is then placed at 4/5 of 25, or 20 inches from the bridge (and 5 inches from the nut). The next note in the chord is 660 cps (E), a ratio of 6/4, and the fret is placed at 2/3 of 25, or 16 2/3 inches from the bridge.
Ranjer Jeometrik guitar necks are not chromatic but "Just-Intoned" to this Harmonic Law, and tuned like sacred Irish harps. Therefore, the lines of a musical staff represent the actual strings. No need for guitar tablatures. By returning to this simple principle, Music can be taught differently, reconnecting to Math and Science through Geometry.
15 FRETS PER OCTAVE