The Open D#7sus tuning offers a unique and resonant sound, famously utilized in 'Opening Mail For My Grandmother' by The Hotelier. This tuning is built around a D#sus4 chord with an added minor seventh, creating a rich, somewhat ambiguous harmonic landscape that's perfect for atmospheric or emo-influenced styles.

Technical Analysis:

• The open strings sound as D# - G# - C# - G# - A# - D# (from low E to high e).
• This configuration forms a D#sus4(b7) chord, also known as D#7sus4:
  • String 6 (D#): Root
  • String 5 (G#): Suspended 4th
  • String 4 (C#): Minor 7th
  • String 3 (G#): Suspended 4th (octave higher than string 5)
  • String 2 (A#): Perfect 5th
  • String 1 (D#): Root (octave higher than string 6)
• The presence of the suspended 4th (G#) and minor 7th (C#) gives the open chord a distinctive, open-ended quality, avoiding the typical major/minor tonality and offering a sense of floating tension.
• The repetition of D# and G# across different octaves provides a full, harmonically stable base, making it easy to create drones and melodic lines that interact with these foundational notes.
• Intervals between strings (low to high):
  • String 6 (D#) to String 5 (G#): Perfect 4th
  • String 5 (G#) to String 4 (C#): Perfect 4th
  • String 4 (C#) to String 3 (G#): Perfect 4th
  • String 3 (G#) to String 2 (A#): Major 2nd
  • String 2 (A#) to String 1 (D#): Perfect 4th

Chordal Possibilities:

• Strumming all open strings yields the beautiful D#sus4(b7), which can serve as a primary open chord.
• By simply barring across any fret, you can easily transpose this unique sus4(b7) chord up the neck. For example, a barre at the 1st fret creates an Esus4(b7), and at the 2nd fret, an Fsus4(b7).
• The two G# notes (strings 5 and 3) and two D# notes (strings 6 and 1) make it easy to create strong, ringing voicings with minimal finger movement, allowing for inventive melodic and rhythmic patterns.
• Experimenting with fretting the major 3rd of the chord (F double sharp or G natural, 3 semitones above D#) could resolve the suspension, leading to a D#7 chord and adding a bluesy or jazzy flavor.
• The closely stacked perfect fourths (strings 6-5, 5-4, 4-3, 2-1) with a single major second break (strings 3-2) allow for interesting arpeggiated figures and modal playing.

How to Tune:

To achieve the Open D#7sus tuning from standard E Standard (E-A-D-G-B-e), follow these steps:

• Low E String (String 6): Tune down 1 semitones to D#3.
• A String (String 5): Tune down 1 semitones to G#3.
• D String (String 4): Tune down 1 semitones to C#4.
• G String (String 3): Tune up 1 semitones to G#4.
• B String (String 2): Tune down 1 semitones to A#4.
• High e String (String 1): Tune down 1 semitones to D#5.

All string movements are minor (1 semitone up or down), making this a safe tuning for standard gauge strings. No special string gauges are typically required as all movements are within +/- 4 semitones.

String 6: D3# (Low D#)

String 5: G3#

String 4: C4#

String 3: G4#

String 2: A4#

String 1: D5# (High D#)