This is the "Shanghai Tuning," a distinctive guitar tuning popularized by the acclaimed fingerstyle guitarist Andy McKee, as described in his composition "The Tuning From Shanghai."

Verbal Analysis:

• The open string notes are E, B, D, G, B, D. This creates a rich, resonant sound that, while not a simple major or minor triad, strongly evokes an E minor 7th chord (E-G-B-D). The 5th (B) and minor 7th (D) are doubled across the strings, giving it a full, sustained quality ideal for percussive and melodic fingerstyle playing.
• The tuning allows for open, ringing harmonies and makes certain chord shapes easily accessible. For instance, the open strings clearly outline an E minor triad (E-G-B) and a G major triad (G-B-D). The low E provides a solid bass foundation for these harmonic possibilities.

Technical Analysis:

• The tuning deviates from standard EADGBe in three key areas:
• The 5th string (normally A2) is raised by 2 semitones to B2.
• The 1st string (normally E4) is lowered by 2 semitones to D4.
• The remaining strings (6th E, 4th D, 3rd G, 2nd B) remain at their standard pitches.
• The resulting open string notes are E2-B2-D3-G3-B3-D4.
• This configuration provides a unique intervallic structure. The presence of the root (E), minor third (G), fifth (B), and minor seventh (D) in the open strings forms an extended Em7 chord, making this a very versatile tuning for melancholic or contemplative pieces.

Tuning Notes:

String 6 (Low E): E2
String 5 (A): B2
String 4 (D): D3
String 3 (G): G3
String 2 (B): B3
String 1 (High E): D4

How to Tune (from Standard EADGBe):

• String 6 (Low E): Keep as is; no change (0 semitones).
• String 5 (A): Tune up 2 semitones to B2.
• String 4 (D): Keep as is; no change (0 semitones).
• String 3 (G): Keep as is; no change (0 semitones).
• String 2 (B): Keep as is; no change (0 semitones).
• String 1 (High E): Tune down 2 semitones to D4.

Note: All string adjustments for this tuning are within a range that generally does not require a change in string gauge. However, always exercise caution when tuning strings up, especially if your guitar is not accustomed to such tension.