The "Modified B Fifths" tuning for Guitar is an adventurous and highly customized setup that deviates significantly from standard guitar tunings, even from a pure fifths tuning. As described, it's an attempt at a B-based fifths tuning designed to be less destructive to the B string, though the high G and E strings might still be under considerable stress due to the drastic changes.

Technical Analysis:

• The open notes are: B1, F#3, C#4, G#4, B3, F#5 (low to high).
• Intervals between adjacent strings reveal the "modified" nature:
  • 6th (B1) to 5th (F#3): A massive interval of two octaves and a perfect fifth (26 semitones). This creates a vast sonic gap, providing a deep, resonant foundation.
  • 5th (F#3) to 4th (C#4): A perfect fifth (7 semitones).
  • 4th (C#4) to 3rd (G#4): A perfect fifth (7 semitones).
  • 3rd (G#4) to 2nd (B3): A significant descending interval of nine semitones, moving from G#4 down to B3. This is a very unconventional drop, dramatically breaking the ascending fifths pattern.
  • 2nd (B3) to 1st (F#5): Another huge interval of two octaves and a perfect fifth (26 semitones), mirroring the wide gap between the lowest string pair.
• The notes present in the open tuning (B, F#, C#, G#) imply a foundation in the key of B major. The full set B1, F#3, C#4, G#4, B3, F#5 gives you multiple octaves of B and F#, and single instances of C# and G#.
• The clustered perfect fifths on strings 5-4-3 (F#3-C#4-G#4) suggest that power chords or fifths-based riffs will be readily accessible and resonant on these middle strings.
• Due to the extreme and non-standard intervals, especially the large jumps and the descending interval between the 3rd and 2nd strings, traditional chord shapes will be largely unusable. This tuning demands an entirely new approach to voicings and fretboard navigation, likely favoring wide-spanning arpeggios, single-note lines, and drone-like textures that exploit the vast open string intervals. The repeating B and F# notes across multiple octaves also facilitate rich, resonant textures.

How to Tune:

Please approach this tuning with care, especially considering the significant changes on some strings. A different string gauge may be advised for strings that are tuned down by more than 4 semitones or up by more than 4 semitones.

• 6th String (Low E): Tune down 5 semitones from E to B1. Caution: Tuning down 5 semitones is a significant change; a heavier gauge string is strongly advised to maintain proper tension and tone.
• 5th String (A): Tune down 3 semitones from A to F#3.
• 4th String (D): Tune down 1 semitone from D to C#4.
• 3rd String (G): Tune up 1 semitone from G to G#4.
• 2nd String (B): Keep as is; no change (0 semitones) to B3.
• 1st String (High E): Tune up 2 semitones from E to F#5.

6th String: B1
5th String: F#3
4th String: C#4
3rd String: G#4
2nd String: B3
1st String: F#5