Repetitive tuning

Repetitive tunings are alternative tunings for the guitar. A repetitive tuning begins with a list of notes that is duplicated, either at unison or at higher octaves.

Among regular tunings, there are four repetitive-tunings (besides trivially repetitive tunings such as C-C-C-C-C-C); this article discusses three minor-thirds tuning, major-thirds tuning, and augmented-fourths tuning (but not major seconds tuning, which is not repetitive on six strings). Among open tunings, there are repetitive versions of open C tuning and open G tuning, which have been associated with the English and Russian guitars, respectively.

Repetition eases the learning of fretboard and chords and eases improvisation. For example, in major-thirds tuning, chords are raised an octave by shifting fingers by three strings on the same frets.

Repetitive tunings are listed after their number of open pitches. For example, the repetitive open-C tuning C-E-G-C-E-G has three open-pitches, each of which is associated with repeated notes {(C,C), (E,E), (G,G)}.

The trivial tuning repeats the same note every string. It is also called a unison regular tuning.

Other trivial-tunings repeat their single notes on a higher octave (or on higher octaves), for example,

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