This is an intricate and sonically rich tuning conceptualized by the legendary Pat Metheny, aptly named "Pat Metheny Half-Nashville Tuning." The name suggests a connection to the high-strung sound of traditional Nashville tuning, where lower strings are often replaced with thinner gauges and tuned an octave higher. In this unique interpretation, the tuning builds upon a B Standard foundation but with significant modifications to the higher strings.

Verbally, this tuning is designed to create expansive, harmonically rich soundscapes that are a hallmark of Metheny's style. It delivers a shimmering, almost harp-like or twelve-string guitar texture, without the actual doubled strings. The selective octave shifts give the guitar a much brighter and more articulate character in its higher range than a typical B Standard tuning, encouraging open harmonies, complex voicings, and ethereal qualities.

Technically, the open strings are set to B1-E2-A3-D4-F4#-B3. While the initial description states it's "B Standard but with the middle two strings up an octave," a closer inspection of the target notes reveals a more extensive revoicing. This tuning takes a full B Standard (B1-E2-A2-D3-F#3-B3) and shifts the four highest strings (A, D, F#, and B) up an entire octave. This results in the A, D, F#, and B strings ringing at A3, D4, F4#, and B3 respectively. The lowest two strings (B1 and E2) remain at their standard B tuning pitches, providing a deep, resonant foundation.

The open string notes (B-E-A-D-F#-B, ignoring octaves for a moment) do not form a simple major or minor chord, indicating a versatile intervallic tuning rather than a drone chord. This structure promotes unique harmonic possibilities and encourages exploration of wider voicings across the fretboard. The dramatic pitch shifts, particularly the highly tensioned A3 and D4, will create a distinct bright and chime-like quality in the upper register. This allows for piano-like sustain and a clarity that sets it apart from more conventional tunings, making it ideal for intricate arpeggios, melodic lines with harmonic support, and creating dense, yet clear, musical textures.

Tuning Notes:

• 6th String (low B): B1
• 5th String (E): E2
• 4th String (A): A3
• 3rd String (D): D4
• 2nd String (F#): F4#
• 1st String (high B): B3

How to Tune (from Standard EADGBe):

To achieve the Pat Metheny Half-Nashville Tuning, adjust your strings as follows:

• 6th String (Low E): Tune down 5 semitones from E2 to B1.
  Note: Tuning down 5 semitones is a significant change. A heavier gauge string is advised for optimal tension and playability.
• 5th String (A): Tune down 5 semitones from A2 to E2.
  Note: Tuning down 5 semitones is a significant change. A heavier gauge string is advised for optimal tension and playability.
• 4th String (D): Tune up 7 semitones from D3 to A3.
  Note: Tuning up 7 semitones is a substantial increase in tension. A lighter gauge string is strongly advised, and proceed with extreme care to avoid string breakage or neck damage.
• 3rd String (G): Tune up 7 semitones from G3 to D4.
  Note: Tuning up 7 semitones is a substantial increase in tension. A lighter gauge string is strongly advised, and proceed with extreme care to avoid string breakage or neck damage.
• 2nd String (B): Tune down 5 semitones from B3 to F#3.
  Note: Tuning down 5 semitones is a significant change. A heavier gauge string is advised for optimal tension and playability. Please be aware of a slight discrepancy in the provided data: while the desired note in the tuning notes is F4#, the tuning movement instruction explicitly states to tune down 5 semitones from B3, which results in F#3. For this 'How to Tune' section, we strictly follow the given string movement.
• 1st String (High E): Tune down 5 semitones from E4 to B3.
  Note: Tuning down 5 semitones is a significant change. A heavier gauge string is advised for optimal tension and playability.

Remember to tune gradually and check your instrument's intonation after making significant pitch changes to maintain playability and protect your guitar.