This is a highly distinctive 7-string guitar tuning, famously associated with jazz virtuoso Charlie Hunter. While drawing inspiration from his unique approach, this particular configuration roots itself around a very low E, providing an incredibly deep and resonant tonal palette suitable for sophisticated jazz, funk, and experimental genres. It allows a single musician to simultaneously handle bass lines, chords, and melodies with remarkable depth and clarity.

Technical Analysis

The tuning features a significant drop across all strings compared to standard tunings, with the lowest string descending to a thunderous E1. This creates a sonic landscape that is notably darker and heavier, enhancing the instrument's bass capabilities.

• Open String Notes: From lowest to highest, the strings are tuned to E1, A1, D2, A2, D3, G3, B3.
• Intervals: The intervals between the open strings are particularly unique and contribute to its characteristic sound:
  • E1 (7th) to A1 (6th) is a Perfect 4th.
  • A1 (6th) to D2 (5th) is a Perfect 4th.
  • D2 (5th) to A2 (4th) is a Perfect 5th.
  • A2 (4th) to D3 (3rd) is a Perfect 4th.
  • D3 (3rd) to G3 (2nd) is a Perfect 4th.
  • G3 (2nd) to B3 (1st) is a Major 3rd.
• Chordal Implications: The repeated A and D notes (A1, A2, D2, D3) are a defining characteristic, offering immediate harmonic stability and flexibility for unique voicings.
  • The open D2-A2-D3 (strings 5, 4, 3) forms a powerful D5 chord, providing a strong anchor for D-based voicings and a solid rhythmic pulse.
  • The combination of E1, A1, D2 (strings 7, 6, 5) creates a deep bass foundation that can imply E minor, E dominant, or even A minor/D major depending on the melodic context.
  • The top three strings, D3, G3, B3 (strings 3, 2, 1), when played open, form a G major triad in first inversion (B-D-G), opening up easy access to G major tonality or complex extensions.
  • Overall, the tuning's architecture facilitates rich, open voicings with deep bass support, ideal for improvisational playing where both rhythm and harmony are maintained by the guitarist.

Open String Notes

Here are the target notes for each string in this unique 7-string tuning, from the lowest (thickest) to the highest (thinnest) string:

• String 7 (Lowest): E1
• String 6: A1
• String 5: D2
• String 4: A2
• String 3: D3
• String 2: G3
• String 1 (Highest): B3

How to Tune Each String

To achieve this specific Charlie Hunter E-Bass 7-String tuning, follow these instructions for each string. Note that all strings require a significant drop in pitch from their standard tuning. For movements exceeding 4 semitones (either up or down), it is strongly recommended to use a heavier gauge string set to maintain proper tension, intonation, and tone, and to avoid string breakage or damage to your instrument.

• String 7 (E1): Tune down 7 semitones. (This is a substantial drop; a very heavy gauge string or even a bass string is advised for optimal performance and to prevent floppiness.)
• String 6 (A1): Tune down 7 semitones. (Again, a substantial drop; heavy gauge recommended.)
• String 5 (D2): Tune down 7 semitones. (Heavy gauge recommended.)
• String 4 (A2): Tune down 5 semitones. (Heavy gauge recommended.)
• String 3 (D3): Tune down 5 semitones. (Heavy gauge recommended.)
• String 2 (G3): Tune down 4 semitones. (A heavier gauge string is recommended for optimal tension.)
• String 1 (B3): Tune down 5 semitones. (Heavy gauge recommended.)