The 8-String Perfect Fourths Tuning: A Logical Expansion with a Twist

The 8-String Perfect Fourths tuning, as described, builds upon the foundational concept of a symmetrical guitar fretboard, extending the range with two additional lower strings. This tuning is designed for players seeking a consistent and predictable layout, which is highly valued in genres like jazz, progressive metal, and experimental music. Its uniformity, across most strings, simplifies the memorization of scales and chord shapes, as patterns can be effortlessly shifted up and down the neck and across the strings.

Technical Analysis: Intervals and Open Chords

While named "8-String Perfect Fourths," a detailed examination of the provided notes reveals a unique interval structure. The tuning features a consistent series of Perfect Fourths (5 semitones) ascending from String 7 (B1) up to String 1 (F4). This means the intervals between String 7 (B1) and String 6 (E2), String 6 (E2) and String 5 (A2), String 5 (A2) and String 4 (D3), String 4 (D3) and String 3 (G3), String 3 (G3) and String 2 (C4), and String 2 (C4) and String 1 (F4) are all perfect fourths. This predominant use of perfect fourths facilitates highly portable chord shapes and scale patterns across these six strings.

However, the interval between the thickest string, String 8 (F#2), and String 7 (B1) is a Perfect Fifth downwards (B1 is a perfect fifth below F#2). This means that String 7 is actually the lowest pitched string in this tuning. This particular configuration results in an overall pitch range spanning from B1 to F4. This unique low interval adds a distinctive harmonic character, distinguishing it from a purely uniform perfect fourths tuning throughout, while still largely embracing the symmetrical fretboard logic. Traditional open major or minor chords are not readily formed in their familiar shapes, encouraging the exploration of quartal harmonies and suspended voicings, which become highly intuitive to construct and transpose.

How to Tune:

To achieve the 8-String Perfect Fourths tuning, follow these precise adjustments from your current setup:

• String 8 (Thickest String): Keep as is; no change (0 semitones). The target note is F#2.
• String 7: Keep as is; no change (0 semitones). The target note is B1.
• String 6: Keep as is; no change (0 semitones). The target note is E2.
• String 5: Keep as is; no change (0 semitones). The target note is A2.
• String 4: Keep as is; no change (0 semitones). The target note is D3.
• String 3: Keep as is; no change (0 semitones). The target note is G3.
• String 2: Tune up 1 semitones. The target note is C4. (If your string is currently B3, tune it up to C4). Note: Tuning up by a small amount like 1 semitone is generally safe for standard gauge strings.
• String 1 (Thinnest String): Tune up 1 semitones. The target note is F4. (If your string is currently E4, tune it up to F4). Note: Tuning up by a small amount like 1 semitones is generally safe for standard gauge strings.

General advice: For tuning movements exceeding 4 semitones up or down, it is advisable to consider a different gauge string to maintain optimal string tension, intonation, and to prevent potential string breakage.

String Notes:

Your 8-string guitar will be tuned as follows, from the thickest (lowest numbered) string to the thinnest (highest numbered) string, with pitches listed from lowest to highest where applicable, but String 7 is the lowest pitched note:

• String 8: F#2
• String 7: B1 (Lowest Pitch in Tuning)
• String 6: E2
• String 5: A2
• String 4: D3
• String 3: G3
• String 2: C4
• String 1: F4