This is an iconic and highly distinctive guitar tuning, famously employed by The Edge of U2 for tracks on their seminal album, "The Unforgettable Fire." As noted in Guitar Player magazine (June 1985), this tuning is a testament to The Edge's innovative approach to guitar voicings, creating atmospheric and expansive soundscapes.

Verbal Analysis

The DGDDAF tuning is a deep and resonant setup, heavily favoring lower notes. It features a significant drop in pitch for most strings, contributing to a rich, almost ambient texture. The repeated D notes on the 6th, 4th, and 3rd strings create a powerful drone foundation, providing a sense of depth and sustained harmony. This tuning doesn't lend itself to conventional open strumming but rather inspires arpeggiated figures, shimmering textures, and unique melodic lines that leverage the specific intervals. The high F string, an unusual choice, adds a distinct color, creating tensions and releases that are characteristic of The Edge's sound, often leaning towards melancholic or ethereal qualities.

Technical Analysis

From low to high, the open strings are: D2 - G2 - D3 - D3 - A3 - F4.

• The lowest three strings (D2-G2-D3) establish a strong open D power chord sound, with the G creating a suspended quality (P4 interval from D2 to G2, P5 from G2 to D3).
• A defining characteristic is the unison D3 notes on both the 4th and 3rd strings. This creates a powerful, droning D that anchors much of the tuning's harmonic character and can be easily exploited for sustained tones or rhythmic patterns.
• The interval from the 3rd string (D3) to the 2nd string (A3) is a perfect 5th, further reinforcing a D-centric tonality.
• The final interval, from the 2nd string (A3) to the 1st string (F4), is a minor 6th. This is highly unconventional for standard tunings and provides the tuning with its unique, slightly melancholic, or ethereal signature, contributing significantly to The Edge's signature sound.

Chordal Potential

While not a simple open major or minor chord, the DGDDAF tuning naturally presents a rich, complex open voicing. The combination of notes D, G, A, and F forms a D minor(add4) or Dsus4(add b3) chord (D-G-D-D-A-F). This suggests that open string arpeggios will sound particularly full and resonant. The duplicated D notes are ideal for creating sustained drones or rhythmic pulses. Standard barre chords would be difficult to transpose effectively, but two- or three-string voicings that leverage the open D and A notes, along with the F, will unlock its distinctive character. The tuning encourages exploration of suspensions, minor tonalities, and atmospheric soundscapes, moving away from traditional chord shapes towards more open, ringing sounds. It's perfectly suited for creating the layered, chiming textures found in U2's early works.

Here are the notes for each string in the DGDDAF tuning:

• 6th String (Low E): D2
• 5th String (A): G2
• 4th String (D): D3
• 3rd String (G): D3
• 2nd String (B): A3
• 1st String (High E): F4

How to Tune to DGDDAF

To achieve The Edge's distinctive DGDDAF tuning from standard E-A-D-G-B-E, follow these specific adjustments for each string. Please take care when making significant changes to string tension, especially when tuning up multiple semitones.

• 6th String (Low E to D): Tune down 2 semitones from E2 to D2.
• 5th String (A to G): Tune down 2 semitones from A2 to G2.
• 4th String (D to D): Keep as is; no change (0 semitones) from D3 to D3.
• 3rd String (G to D): Tune down 5 semitones from G3 to D3. *Caution:* Tuning down 5 semitones is a significant drop. For optimal tone and string life, especially if this tuning is used frequently, considering a heavier gauge string for the 3rd string is advised.
• 2nd String (B to A): Tune down 2 semitones from B3 to A3.
• 1st String (High E to F): Tune up 1 semitone from E4 to F4. Generally, tuning up strings introduces more tension; always tune gradually.

General Gauge Advice: When string movements exceed -4 or +4 semitones from standard tuning, a different gauge string is generally recommended to maintain proper tension, intonation, and string longevity. Tuning up more than 3-4 semitones can be risky for standard gauge strings and the instrument's neck tension.