The Am/Cmaj13 Mm3 Tuning: An Expansive Harmonic Palette for 8-String Guitars

This unique 8-string tuning, named Am/Cmaj13 Mm3, is designed to unlock a vast harmonic landscape, emphasizing both minor and extended major tonalities. As described, it's crafted around the notes of an Am/Cmaj13 chord, promising ease in constructing complex harmonies and melodic lines.

Verbal Analysis

The 'Am/Cmaj13 Mm3' tuning feels incredibly rich and sophisticated, ideal for players looking to delve into jazz, progressive rock, fusion, or even modern classical compositions. The core idea of 'one finger 7th chords, power chords and melodic lines easily' suggests a highly intuitive and ergonomically friendly setup, despite its complexity on paper. This means that once accustomed, chord voicings that would typically require significant finger stretching or tricky positions become readily accessible, allowing for fluid transitions and creative phrasing. The alternating major and minor thirds stack creates a dense, intervallic texture that can be both hauntingly beautiful in minor contexts and brilliantly bright when emphasizing the major aspects. It encourages exploration of arpeggiated patterns and sustained, resonant chords, making it perfect for ambient textures or intricate soloing.

Technical Analysis

This tuning for an 8-string guitar lays out the following open notes, from lowest (8th string) to highest (1st string):

• 8th String: A1
• 7th String: F2
• 6th String: A2
• 5th String: C3
• 4th String: E3
• 3rd String: G3
• 2nd String: B3
• 1st String: D4

When all open strings are played together, the combined notes are A, F, C, E, G, B, D. Arranged from lowest to highest pitch (and within an octave for chord analysis), these are A, B, C, D, E, F, G.

This collection of notes perfectly forms a Cmaj13 chord (C-E-G-B-D-F-A) when C is considered the root, or an Am11 with a flat 6th (A-C-E-G-B-D with F as a b6) when A is the root. The tuning description's 'Am/Cmaj13' is indeed accurate, as all notes necessary for both harmonies are present in the open strings.

The internal structure of the tuning, particularly the 'alternating major and minor thirds' (Mm3), reveals its design for easy chord shapes. Examining the intervals between adjacent strings (from 7th to 1st, after the initial large jump):

• A1 to F2: Minor 6th (9 semitones)
• F2 to A2: Major 3rd (4 semitones)
• A2 to C3: Minor 3rd (3 semitones)
• C3 to E3: Major 3rd (4 semitones)
• E3 to G3: Minor 3rd (3 semitones)
• G3 to B3: Major 3rd (4 semitones)
• B3 to D4: Minor 3rd (3 semitones)

This systematic stacking of thirds, especially from the 7th string upwards, means that barring across several strings can yield rich chord clusters. For instance, a single finger across the 6th, 5th, 4th, 3rd, 2nd, and 1st strings at a given fret will produce a series of stacked thirds, allowing for quick access to complex voicings like 7ths, 9ths, and even 13ths with minimal effort. This design supports the claim of 'one finger 7th chords' and easy 'power chords' (by using adjacent or near-adjacent strings for root-fifth relationships that appear due to the underlying scale). The inherent melodic possibilities are also vast, as the open strings themselves outline a full mode (A Phrygian, or C Lydian for a brighter sound), providing an immediate foundation for improvisation.

How to Tune Your Guitar

Please be cautious when retuning, especially with large semitone changes. If tuning up significantly (more than 4 semitones) or down drastically (more than 4 semitones), consider using a different gauge string to ensure string integrity and optimal tension.

• 8th String (A1): Tune up 3 semitones.
• 7th String (F2): Tune up 6 semitones. Note: A change of this magnitude (6 semitones up) is substantial. Using a heavier gauge string for this position is highly recommended to prevent string breakage and maintain proper tension.
• 6th String (A2): Tune up 5 semitones. Note: A change of this magnitude (5 semitones up) is substantial. Using a heavier gauge string for this position is highly recommended to prevent string breakage and maintain proper tension.
• 5th String (C3): Tune up 3 semitones.
• 4th String (E3): Tune up 2 semitones.
• 3rd String (G3): Keep as is; no change (0 semitones).
• 2nd String (B3): Keep as is; no change (0 semitones).
• 1st String (D4): Tune down 2 semitones.

• String 8: A1
• String 7: F2
• String 6: A2
• String 5: C3
• String 4: E3
• String 3: G3
• String 2: B3
• String 1: D4