The 'Bb 5-6 Tuning' is an open tuning designed to resonate with a rich, full Bb Major (add9) chord when all strings are played open. This creates a beautifully resonant foundation, ideal for singer-songwriters, fingerstyle players, and those looking to explore blues, folk, or even jazz-infused textures.

Technically, the open string notes, from the lowest (6th) to the highest (1st), are: A#2 (Bb2), F2, D3, F3, A#4 (Bb4), C4. When strummed open, these notes collectively form a Bb Major triad (Bb-D-F) with the added 9th (C) and a high octave Bb, providing a lush and harmonically complete sound.

Analyzing the intervals between consecutive strings (ascending from lowest to highest):

• String 6 (Bb2) to String 5 (F2): Perfect 4th (F2 is a P4 up from Bb2)
• String 5 (F2) to String 4 (D3): Major 3rd
• String 4 (D3) to String 3 (F3): Minor 3rd
• String 3 (F3) to String 2 (Bb4): Compound Perfect 4th (a Perfect 4th plus an octave, also known as a P11)
• String 2 (Bb4) to String 1 (C4): Major 2nd

The original description states, "with a 5th and 6th interval between strings 1-2 and 2-3." While the Major 6th interval is present when descending from String 2 (Bb4) to String 3 (F3), and various 5ths are present within the overall chord, the primary strength of this tuning lies in its complete BbMaj(add9) voicing.

The open BbMaj(add9) chord makes this tuning highly versatile for rhythmic strumming and melodic exploration. You can easily create a Bb Major or Bb Major 7 sound by focusing on specific strings or adding minimal fretting. The presence of the drone C on the highest string, as mentioned, offers an excellent melodic anchor or a source of interesting dissonance that can resolve beautifully, enhancing chord changes and lead lines. Sliding this open shape up and down the neck will give you other Major(add9) chords (e.g., Cmaj(add9) at the 2nd fret, Dmaj(add9) at the 4th fret), providing a simplified approach to chord progressions in various keys.

Open String Notes:

• String 6 (Low E): A#2 (Bb2)
• String 5 (A): F2
• String 4 (D): D3
• String 3 (G): F3
• String 2 (B): A#4 (Bb4)
• String 1 (High E): C4

How to Tune from Standard EADGBe:

Please note: This tuning involves significant string tension changes. If tuning a string beyond +/- 4 semitones, it is generally recommended to consider a different string gauge to ensure optimal playability and string longevity, and to avoid potential string breakage or damage to your instrument.

• String 6 (Standard E2): Tune down 6 semitones to A#1 (Bb1). Caution: This is a substantial drop in pitch; a heavier gauge string is strongly advisable.
• String 5 (Standard A2): Tune down 4 semitones to E2. Consider a heavier gauge string for best results.
• String 4 (Standard D3): Keep as is; no change (0 semitones). Stays at D3.
• String 3 (Standard G3): Tune down 2 semitones to F3.
• String 2 (Standard B3): Tune down 1 semitone to A#3 (Bb3).
• String 1 (Standard E4): Tune down 4 semitones to C4. Consider a heavier gauge string for optimal performance.