The "Pentatonic A minor" tuning, also affectionately known as the "Viking Tuning," offers a unique sonic landscape for guitarists. As its name suggests, it is built upon the A minor pentatonic scale (A-C-D-E-G-A), making it inherently melodic and harmonically coherent when strummed open. This tuning is particularly celebrated for its ease in creating resonant fourth and fifth intervals, alongside clear octaves, which contribute to a powerful and ancient sound.

As noted by historically-informed musician Ben Bagby, who utilizes these very intervals in his performances of Beowulf, this tuning can feel both limiting and liberating. While it might pose challenges for intricate modern melodies and complex chord voicings, it simultaneously simplifies the creation of driving rhythmic patterns and strong, open harmonies. The open strings themselves form an A minor pentatonic chord, providing an immediate foundation for folk, blues, or rock styles that lean into modal textures.

Technically, the open string notes are A2, C3, D3, E3, G3, A3. This arrangement means:

• The 6th and 1st strings are tuned to A, providing a strong octave drone.
• The 5th (C) and 2nd (G) strings are a perfect fifth apart, making common blues or rock voicings easily accessible.
• The 6th (A) and 4th (D) strings are a perfect fourth apart, allowing for easy suspension-like sounds or power chord variations.

Open String Notes:

• 6th String (Low E string): A2
• 5th String (A string): C3
• 4th String (D string): D3
• 3rd String (G string): E3
• 2nd String (B string): G3
• 1st String (High E string): A3

How to Tune:

This tuning involves significant changes from standard E Standard tuning. Please proceed with caution, especially with strings that are tuned up or down by 4 semitones or more, as this can affect string tension and potentially require a different gauge of strings for optimal performance and to prevent string breakage.

• 6th String: Tune up 5 semitones from E2 to A2. (Note: Tuning up by 5 semitones is a significant change; consider using a lighter gauge string if this tuning is kept for extended periods.)
• 5th String: Tune up 3 semitones from A2 to C3. (Note: Tuning up by 3 semitones is a moderate change.)
• 4th String: Keep as is; no change (0 semitones). This string remains D3.
• 3rd String: Tune down 3 semitones from G3 to E3. (Note: Tuning down by 3 semitones is a moderate change.)
• 2nd String: Tune down 4 semitones from B3 to G3. (Note: Tuning down by 4 semitones is a significant change; consider a heavier gauge string if this tuning is kept for extended periods.)
• 1st String: Tune down 7 semitones from E4 to A3. (Note: Tuning down by 7 semitones, a perfect fifth, is a very significant change; a heavier gauge string is strongly advised for this string to maintain proper tension and tone.)