The 'Powell' Tuning: A Power Chord Navigator for 7-String Guitar

The 'Powell' tuning is an innovative setup for 7-string guitar, designed with power chord enthusiasts and learners in mind. As described in its conception, it's crafted to enable effortless power chord execution, offering a dual approach: facilitating traditional finger patterns on the higher strings and a 'drop' style fluidity on the lower strings. A significant advantage highlighted by its creator is the clever re-arrangement of intervals, which effectively addresses the commonly encountered 'sudden 4th shift' challenge on the B string (String 2 in standard tunings), thereby simplifying chord learning and fretboard navigation across the instrument.

Technical Analysis: Intervals & Open Chords

This tuning presents a unique intervallic structure across its seven strings, providing distinct sonic and playability characteristics (from lowest to highest string):

• String 7 (G#2) to String 6 (C#3): Perfect Fourth (P4)
• String 6 (C#3) to String 5 (G#3): Perfect Fourth (P4)
• String 5 (G#3) to String 4 (C#4): Perfect Fourth (P4)
• String 4 (C#4) to String 3 (F#4): Perfect Fourth (P4)
• String 3 (F#4) to String 2 (B3): Diminished Fifth (d5) / Augmented Fourth (A4) descending (a substantial drop of 7 semitones)
• String 2 (B3) to String 1 (E4): Perfect Fourth (P4)

The most striking feature is the sequence of four consecutive Perfect Fourths spanning from String 7 (G#2) up to String 3 (F#4). This consistent interval spacing makes playing movable power chords and many modern voicings incredibly intuitive across these five lower strings. A single-finger barre across these strings at any fret will yield a robust voicing of Root-P4-Root-P4-P4 (e.g., fretting at the 2nd fret would give A#, D#, A#, D#, G#), simplifying complex rhythmic riffing and enabling easy transposition of chord shapes.

Following this block of fourths, there's a significant intervallic shift from F#4 (String 3) down to B3 (String 2). This large descending interval is immediately followed by another Perfect Fourth from B3 (String 2) to E4 (String 1), mirroring the highest two strings of a standard guitar tuning. This combination allows for familiar melody lines and chord fragments on the high end while maintaining the ease of power chords and extended range on the low end.

The open strings G#2 C#3 G#3 C#4 F#4 B3 E4 don't form a conventional consonant open chord but rather a complex, open voicing containing G#, C#, F#, B, E. This can be utilized for dissonant textures or, more practically, provides a flexible foundation for fretted chords where the consistent P4 intervals on the lower strings make root-fourth type voicings extremely accessible.

How to Tune Your Guitar to 'Powell'

To achieve the 'Powell' tuning, adjust your 7-string guitar as follows. Please ensure your strings are in good condition, especially for downward tunings.

• String 7 (Lowest): Tune to G#2. Tune down 3 semitones.
• String 6: Tune to C#3. Tune down 3 semitones.
• String 5: Tune to G#3. Tune down 1 semitone.
• String 4: Tune to C#4. Tune down 1 semitone.
• String 3: Tune to F#4. Tune down 1 semitone.
• String 2: Tune to B3. Keep as is; no change (0 semitones).
• String 1 (Highest): Tune to E4. Keep as is; no change (0 semitones).

Note: All string movements for this tuning are within reasonable limits for standard string gauges. However, always exercise care when adjusting string tension.

String 7 (Lowest): G#2

String 6: C#3

String 5: G#3

String 4: C#4

String 3: F#4

String 2: B3

String 1 (Highest): E4