The tuning for this 9-string Guitar is aptly named "Abyssal Nine-String Experiment". As indicated by its original description from the user, it's an experimental setup, not necessarily designed for conventional play but rather to explore the extreme sonic capabilities of an extended-range instrument. It delves into very low frequencies, with the deepest string tuned to C1, setting a dark and profound foundation.

Technical Analysis

This 9-string tuning presents a unique and largely dissonant intervallic structure across its open strings, moving from the very low C1 to a ringing G4. The full open tuning is C1 A1 B1 B1 E2 D3 F3 A3 G4. This wide range spans over four octaves. The presence of two B1 strings (strings 7 and 6) is an interesting feature, creating a thick unison or octave potential in the lower register. Examining the intervals between adjacent strings reveals a non-standard approach:

• String 9 to 8 (C1 to A1): Major 6th (10 semitones)
• String 8 to 7 (A1 to B1): Major 2nd (2 semitones)
• String 7 to 6 (B1 to B1): Unison (0 semitones)
• String 6 to 5 (B1 to E2): Perfect 4th (5 semitones)
• String 5 to 4 (E2 to D3): Major 7th (11 semitones) - effectively a minor 2nd down, creating a very wide gap.
• String 4 to 3 (D3 to F3): Minor 3rd (3 semitones)
• String 3 to 2 (F3 to A3): Major 3rd (4 semitones)
• String 2 to 1 (A3 to G4): Minor 7th (10 semitones)

The overall tuning does not immediately lend itself to common open position chords, suggesting it's tailored for specific riffing, melodic lines, or creating rich, often dissonant, harmonic landscapes in an extended range context. The wide jumps and non-standard intervals make traditional chord shapes challenging, but also open doors for unique voicings.

Chordal Possibilities

While not a "chord-friendly" open tuning in the traditional sense, some interesting harmonic clusters and open chords can be identified or are within reach:

• The most immediately playable open chord is found on strings 4, 3, and 2: D3 - F3 - A3. This forms an open D minor triad, offering a clear and resonant minor tonality in the mid-range.
• The lowest strings (C1, A1, B1, B1, E2) create a powerful, low-end cluster. While not a conventional chord, C1-E2 (string 9 and 5) gives a C-E major third interval, which could anchor a C major or C minor idea if other notes are added.
• The unison B1s on strings 7 and 6 could be leveraged for massive, thick low-end drones or riffs, especially combined with the C1 below it (C1-B1 creates a haunting major 7th interval).
• Given the broad range, power chords and octave shapes will be highly effective. For example, a partial C power chord (C1 and G2 if fretted on string 5 at 7th fret) would resonate with immense depth.

How to Tune Your Guitar

To achieve the "Abyssal Nine-String Experiment" tuning, carefully adjust each string from its implied standard note. Please be mindful of string tension, especially for larger movements. For changes exceeding 4 semitones up or down, it is generally recommended to consider using a different string gauge to avoid breakage or intonation issues.

• String 9 (Lowest): Your string is likely tuned to C sharp 1 (C#1). Tune down 1 semitones to reach C1. This is a minor adjustment.
• String 8: Your string is likely tuned to F sharp 1 (F#1). Tune up 3 semitones to reach A1. Exercise caution as tuning up multiple semitones increases tension.
• String 7: Your string is likely tuned to B1. Keep as is; no change (0 semitones).
• String 6: Your string is likely tuned to E2. Tune down 5 semitones to reach B1. This is a significant drop; consider a heavier gauge string if this is a permanent tuning.
• String 5: Your string is likely tuned to A2. Tune down 5 semitones to reach E2. Another substantial drop; a heavier gauge string is advised here.
• String 4: Your string is likely tuned to D3. Keep as is; no change (0 semitones).
• String 3: Your string is likely tuned to G3. Tune down 2 semitones to reach F3.
• String 2: Your string is likely tuned to B3. Tune down 2 semitones to reach A3.
• String 1 (Highest): Your string is likely tuned to E4. Tune up 3 semitones to reach G4. As with string 8, be careful with increased tension.

This tuning, with its deep notes and unconventional intervals, is perfect for exploring extended-range guitar's potential in progressive, metal, or experimental genres. Enjoy the journey into the abyss!

String 9: C1 (Lowest String)
String 8: A1
String 7: B1
String 6: B1
String 5: E2
String 4: D3
String 3: F3
String 2: A3
String 1: G4 (Highest String)