The D2-F4 9 String ALT 3rds tuning presents a fascinating and highly organized approach for a 9-string guitar, creating a rich harmonic palette suitable for a wide array of musical genres, particularly those requiring complex voicings and lush harmonies such as jazz, funk, or progressive styles.

Verbal Analysis

This tuning, extending from a very low D1 to a relatively high F3 across nine strings, opens up a massive sonic range for the instrument. Its structure, primarily built on alternating minor and major third intervals, makes for an incredibly intuitive playing experience once the initial learning curve of non-standard tuning is overcome. Players will find that complex chords, especially 7th chords, become easily accessible with minimal finger movement across the fretboard. This encourages a very open, resonant sound and facilitates quick harmonic changes, making it ideal for arpeggiated figures, chord-melody playing, and experimental soundscapes. The wide intervallic jumps between strings might initially feel unfamiliar but quickly reveal a logical and musically rich layout.

Technical Analysis

This tuning is fundamentally structured around a sequence of alternating minor and major third intervals. The full sequence of open notes from the lowest (9th) to the highest (1st) string is D1, F1, A1, C2, E2, G2, B2, D3, F3. Let's break down the intervals between adjacent strings:

• String 9 (D1) to String 8 (F1): Minor 3rd (3 semitones)
• String 8 (F1) to String 7 (A1): Major 3rd (4 semitones)
• String 7 (A1) to String 6 (C2): Minor 3rd (3 semitones)
• String 6 (C2) to String 5 (E2): Major 3rd (4 semitones)
• String 5 (E2) to String 4 (G2): Minor 3rd (3 semitones)
• String 4 (G2) to String 3 (B2): Major 3rd (4 semitones)
• String 3 (B2) to String 2 (D3): Minor 3rd (3 semitones)
• String 2 (D3) to String 1 (F3): Minor 3rd (3 semitones)

As observed, the pattern is predominantly an alternation of minor and major thirds, with the exception of the very last interval (D3-F3) which is also a minor third. This highly consistent pattern is what makes the tuning so powerful for chord voicings.

A standout feature, as described in the tuning's original notes, is that "every four strings in the same fret forms a minor triad + b7 or a major triad + 7 depending on the string starting." This means:

• Fretting strings 9-6 at the same fret will yield a Minor 7th chord (e.g., open strings: Dm7 = D-F-A-C).
• Fretting strings 8-5 at the same fret will yield a Major 7th chord (e.g., open strings: Fmaj7 = F-A-C-E).
• This pattern continues up the neck, making it incredibly simple to form jazz chords and extended harmonies with simple barre shapes or minimal finger stretches. This uniformity allows for easy transposition and encourages exploration of harmonic progressions across the entire neck.

Open Chords and Reachable Voicings

The open strings themselves offer a wealth of readily available 7th chords due to the consistent intervallic structure:

• Strings 9-6 (D1-F1-A1-C2): D Minor 7th (Dm7)
• Strings 8-5 (F1-A1-C2-E2): F Major 7th (Fmaj7)
• Strings 7-4 (A1-C2-E2-G2): A Minor 7th (Am7)
• Strings 6-3 (C2-E2-G2-B2): C Major 7th (Cmaj7)
• Strings 5-2 (E2-G2-B2-D3): E Minor 7th (Em7)
• Strings 4-1 (G2-B2-D3-F3): G Major 7th (Gmaj7)

Beyond the open position, players can quickly form these same 7th chords by simply barring four adjacent strings at any fret. This consistency removes much of the complexity often associated with playing jazz or extended chords, making them highly accessible for improvisation and composition.

How to Tune

To achieve the D2-F4 9 String ALT 3rds tuning, follow these specific instructions for each string, from the lowest (9th) to the highest (1st):

• 9th String (Lowest): Tune to D1. This requires you to Tune up 1 semitones.
• 8th String: Tune to F1. This requires you to Tune down 1 semitones.
• 7th String: Tune to A1. This requires you to Tune down 2 semitones.
• 6th String: Tune to C2. This requires you to Tune down 4 semitones.
• 5th String: Tune to E2. This requires you to Tune down 5 semitones. Caution: Tuning down 5 semitones is a significant change. A different string gauge may be advised for optimal tension and tone.
• 4th String: Tune to G2. This requires you to Tune down 7 semitones. Caution: Tuning down 7 semitones is a significant change. A different string gauge may be advised for optimal tension and tone.
• 3rd String: Tune to B2. This requires you to Tune down 8 semitones. Caution: Tuning down 8 semitones is a significant change. A different string gauge may be advised for optimal tension and tone.
• 2nd String: Tune to D3. This requires you to Tune down 9 semitones. Caution: Tuning down 9 semitones is a significant change. A different string gauge may be advised for optimal tension and tone.
• 1st String (Highest): Tune to F3. This requires you to Tune down 11 semitones. Caution: Tuning down 11 semitones is a significant change. A different string gauge may be advised for optimal tension and tone.

Here are the open notes for each string in this tuning, from lowest (9th) to highest (1st):

• 9th String: D1
• 8th String: F1
• 7th String: A1
• 6th String: C2
• 5th String: E2
• 4th String: G2
• 3rd String: B2
• 2nd String: D3
• 1st String: F3