This is a highly distinctive and resonant tuning, famously used by fingerstyle virtuoso Don Ross for his track "Rockbarra". It presents a dark, expansive soundscape, leaning towards a minor tonality with rich harmonic possibilities. The significantly lowered bass strings provide a deep, percussive foundation, while the varied intervals across the fretboard offer unique voicings for chords and melodic lines. It’s a tuning designed for expressive, open-string work and intricate fingerstyle arrangements.

The tuning notes are C2-G2-D#4-F3-G3-A#4. Analyzing the intervals from the lowest C2:

• String 6 (C2): Root
• String 5 (G2): Perfect 5th, creating a strong C5 power chord with the lowest string.
• String 4 (D#4): Minor 3rd (relative to C2, but two octaves higher). This interval strongly suggests a C minor tonality.
• String 3 (F3): Perfect 4th, adding a characteristic 'sus4' or 'add11' flavor.
• String 2 (G3): Octave of the 5th, reinforcing the C tonality.
• String 1 (A#4): Minor 7th (relative to C2, but three octaves higher). This completes a C minor 7 harmonic structure.

The overall harmonic content of the open strings includes C, D#, F, G, A#, which aligns with a C minor 7 (add11) chord (C-D#-G-A# with an added F). The spread of notes across octaves (D#4 and A#4 being very high) creates a wide sonic panorama, ideal for intricate fingerstyle melodies to sing over a deep, resonant bass.

Open Chord Possibilities:

• A full strum of the open strings will yield a complex C minor 7 (add11) voicing, rich with overtones due to the wide intervallic spread.
• Barring across the fretboard at any position will produce unique, often dense, chord voicings. For instance, a barre at the 3rd fret would yield D#-A#-G-A#-C#-D#, which outlines an an Eb major 7(sus4) or similar.
• The low C-G (strings 6 & 5) provide an excellent foundation for power chords or root-fifth basslines, allowing for melodic exploration on the higher strings.
• Shapes involving the D# (String 4) and A# (String 1) will naturally lend themselves to minor or dominant 7th harmonies, providing a melancholic or bluesy feel.

Open String Notes:

String 6: C2

String 5: G2

String 4: D#4

String 3: F3

String 2: G3

String 1: A#4

How to Tune (from Standard EADGBe):

• String 6 (Low E): Tune down 4 semitones to C2. This is a significant drop, so proceed with care.
• String 5 (A): Tune down 2 semitones to G2.
• String 4 (D): Tune up 1 semitone to D#3. (Note: The target note in the "Open String Notes" section is D#4, which cannot be achieved by tuning up 1 semitone from a standard D3 string).
• String 3 (G): Tune down 2 semitones to F3.
• String 2 (B): Tune down 4 semitones to G3. This is a significant drop, so proceed with care.
• String 1 (High E): Tune down 6 semitones to A#3. This is a very significant drop (a tritone). We recommend using a heavier gauge string to avoid excessive slack and ensure proper intonation and playability. (Note: The target note in the "Open String Notes" section is A#4, which cannot be achieved by tuning down 6 semitones from a standard E4 string).

Important Tuning Note: When tuning strings down by 4 or more semitones, or up by 3 or more semitones, we generally advise caution. For movements exceeding 4 semitones (either up or down), consider using a different gauge string to maintain optimal tension and prevent potential string damage or poor intonation.