The "Open F#Maj9" tuning is described as an open tuning where strumming the strings produces a rich and bright chord, excellent for solo guitar improvisation. While the name suggests an F# Major 9th chord, a technical analysis of the open string notes reveals a slightly different harmonic structure that offers a unique character.

The open strings are tuned to C#3, F#3, A#3, G#4, C#5, F4 (from low 6th string to high 1st string). When these notes are stacked, they form an F# dominant 9th (F#9) chord. The constituent intervals are: F# (Root), A# (Major 3rd), C# (Perfect 5th), F (Minor 7th), and G# (Major 9th). The presence of the minor seventh (F) is what gives this tuning its dominant quality, imparting a bluesy, jazzy, or fusion character rather than the purely bright and resolved sound of a Major 9th. The low C# and F# on strings 6 and 5 provide a strong, resonant foundation, with the C# repeated on string 2 for added fullness.

This dominant 9th voicing offers a versatile sonic palette. Its inherent tension and colorful extensions (the G# 9th and F b7th) make it particularly suitable for improvisational solos, creating interesting harmonies and melodic lines over blues, jazz, or funk progressions. The open chord itself is powerful, and subtle fingerings can easily lead to other dominant 9th chords up the neck by simply barring across frets. For instance, barring all strings at the 2nd fret would yield a G#9 chord, expanding the harmonic possibilities with relative ease across the fretboard.

The unique intervallic relationships across the strings, such as the perfect fourth between C# and F#, the major third between F# and A#, and the minor second between A# and G#, invite exploration of unusual voicings and melodic patterns that would be challenging to achieve in standard tuning. This makes it an inspiring tuning for guitarists looking to break out of conventional shapes and discover fresh, harmonically rich sounds.

Tuning Notes

The open strings for this tuning are as follows (from low 6th string to high 1st string):

• String 6 (Low E): C3#
• String 5 (A): F3#
• String 4 (D): A3#
• String 3 (G): G4#
• String 2 (B): C5#
• String 1 (High E): F4

How to Tune for Open F#Maj9

To achieve the Open F#Maj9 tuning from standard EADGBe tuning, follow these instructions carefully. Always tune slowly and check your intonation with a reliable tuner.

• String 6 (Low E): Tune this string down 3 semitones from standard E to C#3.
• String 5 (A): Tune this string down 3 semitones from standard A to F#3.
• String 4 (D): Tune this string down 4 semitones from standard D to A#3. Note: Tuning down 4 semitones is a significant change. If you plan to use this tuning frequently, consider using a heavier gauge string for optimal tension and tone, as the string may feel quite loose otherwise.
• String 3 (G): Tune this string up 1 semitone from standard G to G#4.
• String 2 (B): Tune this string up 2 semitones from standard B to C#5.
• String 1 (High E): Tune this string up 1 semitone from standard E to F4.

Always exercise caution when tuning strings up, as this increases tension on the string and the guitar neck. While the upward movements here are minor, generally, tuning up more than 3 or 4 semitones from standard may require a lighter gauge string to prevent undue stress or breakage.