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Jackson 7-String 11-Limit Split-Fret (2022)

This seven-string uses a fixed Otonal tuning of harmonics 2-3-4-5-7-9-11 of a 30Hz fundamental.  This aligns within 150 cents of the standard tuning, allowing string gauges and saddles to be relatively untouched.  

Scroll down to see the full pitch-map of the fretting.


7-String Split-Fret Scale

The "split-frets" (partial frets) are chosen for each of the strings with a preference for simple 11-Limit pitches.

For example, many of the X/11 frets appear on the highest string (tuned to harmonic 11) where the resulting pitch is a simple harmonic on that string [e.g., 14/11 on the 11-string = 14th harmonic]. 

The pitch map below chows each fret (on the rows), each string (the column-groups) as HEJI pitches, ratios from the 30Hz fundamental, and frequencies.

Jackson 7-String FULL Tuning_Pitches_Frequencies.jpg
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