Tuning Overview: Alternating Thirds 9-String Drop Tuning

This is an exceptionally deep and harmonically rich 9-string guitar tuning, spanning an impressive range from a rumbling D1 to a bright F#4. Dubbed "Alternating Thirds 9-String Drop Tuning," it lives up to its name by featuring a consistent pattern of alternating minor and major third intervals across all strings. This creates a dense, intervallic landscape, perfect for exploring complex jazz voicings, progressive metal textures, or ambient soundscapes.

Technical Analysis

The open string configuration is D1-F1-A1-C2-E2-G2-B2-D3-F#4. Analytically, the intervals between adjacent strings are:

• 9th to 8th String (D1 to F1): Minor 3rd (3 semitones)
• 8th to 7th String (F1 to A1): Major 3rd (4 semitones)
• 7th to 6th String (A1 to C2): Minor 3rd (3 semitones)
• 6th to 5th String (C2 to E2): Major 3rd (4 semitones)
• 5th to 4th String (E2 to G2): Minor 3rd (3 semitones)
• 4th to 3rd String (G2 to B2): Major 3rd (4 semitones)
• 3rd to 2nd String (B2 to D3): Minor 3rd (3 semitones)
• 2nd to 1st String (D3 to F#4): Major 3rd (4 semitones)

As the original description notes, this structure makes it exceptionally easy to form rich chords. Every four strings at the same fret will naturally form either a minor 7th (e.g., D1-F1-A1-C2 forms Dm7) or a major 7th chord (e.g., C2-E2-G2-B2 forms CMaj7, or G2-B2-D3-F#4 forms GMaj7). This simplifies chord voicings significantly, allowing for complex harmonic structures to be played with relative ease across wide string sets. Open position chords are particularly lush:

• Strings 9-6 (D1-F1-A1-C2): A clear D minor 7th chord.
• Strings 8-5 (F1-A1-C2-E2): An F Major 7th chord (F-A-C-E).
• Strings 7-4 (A1-C2-E2-G2): An A minor 7th chord (A-C-E-G).
• Strings 6-3 (C2-E2-G2-B2): A C Major 7th chord (C-E-G-B).
• Strings 5-2 (E2-G2-B2-D3): An E minor 7th chord (E-G-B-D).
• Strings 4-1 (G2-B2-D3-F#4): A G Major 7th chord (G-B-D-F#).

This open tuning provides immediate access to a vast array of harmonically sophisticated sounds, ideal for composers and players seeking unconventional sonic palettes.

How to Tune

This tuning involves significant string tension changes, particularly for the higher strings. Please tune carefully and consider a different string gauge for strings that require large downward adjustments to maintain proper tension and intonation.

• 9th String (Lowest): To tune your 9th string to D1, you must Tune up 1 semitone.
• 8th String: To tune your 8th string to F1, you must Tune down 1 semitone.
• 7th String: To tune your 7th string to A1, you must Tune down 2 semitones.
• 6th String: To tune your 6th string to C2, you must Tune down 4 semitones. Exercise caution as this is a significant drop; a heavier gauge string may be advisable.
• 5th String: To tune your 5th string to E2, you must Tune down 5 semitones. A different string gauge is strongly advised for this substantial drop to ensure proper playability and string longevity.
• 4th String: To tune your 4th string to G2, you must Tune down 7 semitones. A different string gauge is strongly advised for this substantial drop.
• 3rd String: To tune your 3rd string to B2, you must Tune down 8 semitones. A different string gauge is strongly advised for this substantial drop.
• 2nd String: To tune your 2nd string to D3, you must Tune down 9 semitones. A different string gauge is strongly advised for this substantial drop.
• 1st String (Highest): To tune your 1st string to F#4, you must Tune down 10 semitones. A different string gauge is strongly advised for this extreme drop.

The open strings for this 9-string guitar tuning are:

• 9th String: D1 (Lowest)
• 8th String: F1
• 7th String: A1
• 6th String: C2
• 5th String: E2
• 4th String: G2
• 3rd String: B2
• 2nd String: D3
• 1st String: F#4 (Highest)