Tuning Analysis: Cm6/9

This unique guitar tuning, aptly named 'Cm6/9', presents an intriguing blend of heavy, low-end power and melancholic open sonorities. As described by its inventor, it aims to fuse the 'Ava Gardner' power chord bass strings popularized by The Melvins with a 'Nick Drake-ish open sus chord' feel. The resulting open voicing is a rich and complex C minor 6/9 chord, offering a distinctive palette for musical exploration.

Technical Observations:

The open strings are tuned to C2-G2-D3-D4#-A3-D4 (from the 6th string, low E, to the 1st string, high E).
The lowest three strings (C2-G2-D3) form a robust power chord foundation. Specifically, the C2-G2 interval is a perfect fifth, and G2-D3 is also a perfect fifth, effectively creating a C5 power chord extended into the bass, providing a strong, resonant low end.
The overall notes present in the open tuning are C, G, D, D#, and A. When arranged, these notes form C-D-D#-G-A, which are the root, 9th, minor 3rd (D# is enharmonically Eb), 5th, and 6th of a C minor chord, hence the precise Cm6/9 designation.
A particularly striking and characteristic feature of this tuning is the interval between the 4th string (D3) and the 3rd string (D4#). This is a compound minor 2nd (D to Eb), creating a highly dissonant and tension-filled interval that adds a dark, expressive character to the open chord. This specific interval is central to the tuning's unique texture and harmonic tension.
The higher strings (A3-D4) form a perfect 4th, an interval commonly found in suspended chords, which contributes to the 'Nick Drake-ish' melodic potential mentioned in the tuning's description.

Open Chords and Voicings:

The open tuning itself presents a full C minor 6/9 chord, ready to be strummed for a dark, sophisticated harmonic foundation. Due to the irregular intervals between strings, especially the D3-D4# relationship, traditional chord shapes will be significantly transformed, opening up new sonic possibilities. Barre chords across the fretboard will yield different inversions or extensions of the Cm6/9 shape, transposed to new roots. Experimentation with two- or three-string voicings, particularly on the lower strings for powerful, resonant chords or higher strings for melodic fragments, will unlock the full expressive potential of this tuning.

How to Tune:

To achieve the 'Cm6/9' tuning from standard EADGBe, follow these precise string movements:

• 6th String (Low E): Tune down 4 semitones from E2 to C2. Caution: Dropping four semitones is a significant change; consider a heavier gauge string to maintain adequate tension and tone, or proceed with care.
• 5th String (A): Tune down 2 semitones from A2 to G2.
• 4th String (D): Keep as is; no change (0 semitones) from D3 to D3.
• 3rd String (G): Tune down 4 semitones from G3 to D4#. Caution: Dropping four semitones for a G string is a considerable change; a lighter gauge string might be advisable for better playability and to avoid excessive slack.
• 2nd String (B): Tune down 2 semitones from B3 to A3.
• 1st String (High E): Tune down 2 semitones from E4 to D4.