Verbal Description

This is an exceptionally deep and unconventional 9-string tuning, designed for players seeking an extreme low end and a highly unique sonic palette. It ventures into the sub-bass realm with its lowest note, creating a truly 'abyssal' foundation. The irregular and wide intervals across the strings foster a dense, complex soundscape, making it ideal for experimental, heavy, or atmospheric genres.

Technical Analysis

This 9-string tuning features a starting point of F0 on the lowest string, pushing the boundaries of typical guitar range. The open notes are F0, A#1, D#2, G#2, C#3, F#3, B2, E3, and G#4 (from lowest to highest).

Intervallic Structure (from lowest to highest string):

• String 9 (F0) to String 8 (A#1/Bb1): A very wide interval of a compound major third (octave plus major third), spanning 15 semitones.
• Strings 8 (A#1/Bb1) to 4 (F#3/Gb3): These five strings are consistently tuned in perfect fourths (A#1-D#2, D#2-G#2, G#2-C#3, C#3-F#3). This creates a strong, modern intervallic stack.
• String 4 (F#3/Gb3) to String 3 (B2): A significant downward shift, moving down a major sixth (7 semitones). This creates a large gap in the sequence.
• String 3 (B2) to String 2 (E3): A perfect fourth.
• String 2 (E3) to String 1 (G#4/Ab4): Another substantial upward leap, a compound major third (octave plus major third), covering 15 semitones.

Open Chords and Voicings:

Given its unique and often wide intervallic structure, this tuning does not typically form common open major or minor chords across all strings. Instead, it offers distinct sonic possibilities:

• Sub-Bass Foundation: The F0 on the lowest string provides an incredibly deep, fundamental drone or bass note that can underpin extremely heavy arrangements.
• Quartal Harmony: The stack of perfect fourths from String 8 to String 4 (A#1, D#2, G#2, C#3, F#3) is ideal for generating dense, modern, and often suspended or dissonant voicings. These are characteristic of jazz, fusion, and experimental music, creating rich, open-ended textures when played together.
• Split Register Play: The significant jumps between String 4 and 3, and String 2 and 1, encourage separating the fretboard into distinct tonal areas. This allows for complex polyphonic or layered approaches, such as using the lowest strings for heavy riffs while higher strings play melodic lines or atmospheric textures.
• Intentional Dissonance and Drones: The combination of extreme low and high notes, coupled with irregular intervals, makes this tuning highly effective for creating dramatic tension, expansive atmospheric soundscapes, and sustained drones with a unique character.

This tuning is best suited for musicians engaged in experimental, avant-garde, djent, or extreme metal genres who aim to explore new sonic territories beyond traditional guitar harmony.

How to Tune

Important Note: This tuning involves significant string tension changes, as all strings are tuned down by 7 or 8 semitones. For optimal playability and to prevent excessive string floppiness, especially for the lowest strings, it is highly recommended to use a heavier gauge string set specifically designed for extremely low tunings. Always exercise caution when making large tuning adjustments.

• String 9 (Lowest String): Tune down 8 semitones to F0.
• String 8: Tune down 8 semitones to A#1.
• String 7: Tune down 8 semitones to D#2.
• String 6: Tune down 8 semitones to G#2.
• String 5: Tune down 8 semitones to C#3.
• String 4: Tune down 8 semitones to F#3.
• String 3: Tune down 8 semitones to B2.
• String 2: Tune down 7 semitones to E3.
• String 1 (Highest String): Tune down 8 semitones to G#4.

String 9 (Lowest): F0

String 8: A#1

String 7: D#2

String 6: G#2

String 5: C#3

String 4: F#3

String 3: B2

String 2: E3

String 1 (Highest): G#4

Note: Tuning down by 4 or more semitones (as seen across all strings here) often requires a heavier string gauge to maintain adequate tension and prevent string flop, especially for the lower strings.