Neutral third cents and are difficult for most people to distinguish by ear. Neutral thirds are roughly a quarter tone sharp from 12 equal temperament minor thirds and a quarter tone flat from 12-ET major thirds. In just intonation, as well as in tunings such as 31-ET, 41-ET, or 72-ET, which more closely approximate just intonation, the intervals are closer together. Neutral thirds expressed in the form of a ratio of two whole numbers can also be considered as the interval between the harmonics of the same order. For instance, an undecimal neutral third, with a ratio of 11:9, is the interval
Major thirds tuning improvisation. In contrast, chords cannot be shifted around the fretboard in standard tuning, which requires four chord-shapes for the major chords: There are separate fingerings for chords having root notes on one of the four strings three–six. The repetition of the major-thirds tuning enables notes and chords to be raised one octave by being "vertically" shifted by three strings. Notes and chords may be shifted "diagonally" in major-thirds tuning, by combining a vertical shift of one string with a horizontal shift of four frets: "Like all regular tunings, chords in the major third tuning can be moved across the fretboard