The D Major Extended Open tuning, also known by its note sequence DF#C#EGE, transforms the standard guitar into a rich harmonic landscape, primarily rooted in D Major. It's a versatile tuning that blends familiar open string resonances with intriguing harmonic possibilities.

Verbal Analysis

This tuning immediately presents a full, resonant sound when strummed open. The presence of D, F#, and C# gives it a strong D Major 7th character, while the additional E and G create suspended and added tones, lending a sophisticated, almost orchestral quality. The open strings can form a beautiful Dmaj7sus2sus4 chord (D F# C# E G E), providing a wide, open voice that's perfect for ambient soundscapes, fingerstyle arrangements, or powerful open chord voicings. The low D string establishes a solid bass foundation, reminiscent of Drop D tunings, which can make for powerful riffs and melodic bass lines.

Playing in this tuning encourages exploration beyond conventional chord shapes. Open string drones can be easily combined with single-note melodies. Chords like D Major, D Major 7, E minor, and G major can be found or easily implied, often with open strings enriching their voicings. For instance, a simple two-finger shape on strings 3 and 2 could yield interesting clusters against the open D, F#, C#, and E. Barring across certain frets will produce unique extended chords, opening up new sonic textures for creative composition.

Technical Analysis

The open notes for this tuning are: D2 - F#3 - C#4 - E3 - G3 - E4 (from thickest to thinnest string).

• String 6 (Low D): Tuned down from E to D (a whole step). This provides a deep, resonant bass, common in many alternate tunings.
• String 5 (F#): Tuned down from A to F# (a minor third). This interval (D to F#) forms a major third, establishing the D Major tonality.
• String 4 (C#): Tuned down from D to C# (a half step). This creates a major seventh interval with the low D, contributing to the Dmaj7 sound. Interestingly, the C# is lower in pitch than the E on the 3rd string.
• String 3 (E): Tuned down from G to E (a minor third). This E acts as the 2nd (or 9th) of D, adding suspension and brightness.
• String 2 (G): Tuned down from B to G (a major third). This G functions as the 4th (or 11th) of D, further expanding the harmonic palette.
• String 1 (High E): Remains at standard E. This high E provides a familiar reference point and complements the D Major context as a major 2nd (9th).

The intervalic structure from low D (D-F#-C#-E-G-E) reveals a complex stack: Root, Major 3rd, Major 7th, Major 9th, Perfect 11th, and an octave higher Major 9th. This creates a Dmaj7sus2sus4 chord when strummed open, offering a rich, extended harmony without needing to fret any notes. The repeated E's (E3 and E4) and the F# and G on adjacent strings create interesting close voicings and potential for ringing harmonies.

How to Tune

To achieve the D Major Extended Open tuning from standard EADGBe, follow these string adjustments. Please note that significant downward tuning can sometimes cause strings to feel slacker, and very large changes (beyond +/- 4 semitones) may benefit from a different string gauge for optimal tension and tone.

• String 6 (Low E): Tune down 2 semitones to D2.
• String 5 (A): Tune down 3 semitones to F#3.
• String 4 (D): Tune down 1 semitone to C#4.
• String 3 (G): Tune down 3 semitones to E3.
• String 2 (B): Tune down 4 semitones to G3. Care should be taken with this adjustment. For extended use, considering a slightly heavier gauge string for optimal tension may be beneficial.
• String 1 (High E): Keep as is; no change (0 semitones) to E4.

String 6 (Low String): Originally E2, this string is tuned down 2 semitones to D2, establishing the deep root of the tuning.

String 5: Originally A3, this string is tuned down 3 semitones to F#3, contributing the crucial major third to the D tonic.

String 4: Originally D4, this string is tuned down 1 semitone to C#4, providing the leading tone/major seventh for the D Major harmony.

String 3: Originally G3, this string is tuned down 3 semitones to E3, functioning as the 2nd/9th of D, adding brightness and suspension.

String 2: Originally B3, this string is tuned down 4 semitones to G3, serving as the 4th/11th of D, further expanding the harmonic possibilities.

String 1 (High String): Originally E4, this string remains unchanged (0 semitones) at E4, providing an upper voice that reinforces the 2nd/9th of D and the suspended quality.