This unique tuning, aptly named Open C#m9, is a personal favorite designed to deliver a rich and complex chord with a single strum of the open strings. As the creator describes, "C#m9 is my favourite tuning so I've decided to make it a open guitar tuning." It offers a sophisticated sound, perfect for adding depth and emotional resonance to various genres from jazz and blues to atmospheric soundscapes or modern rock where a darker, full harmonic texture is desired.

Technical Analysis of Open C#m9 Tuning

When all strings are strummed open, this tuning produces a beautiful and full C# minor 9th chord with an E bass note (C#m9/E). The notes from lowest to highest, as provided in the tuning, are:

• E2 (Low E)
• G3# (G sharp)
• C4# (C sharp)
• E3 (E)
• B3 (B)
• D5# (D sharp)

The individual notes present across these strings are E, G#, B, C#, and D#. When analyzed from a C# root, these perfectly align with the intervals of a C# minor 9th chord:

• C# (Root)
• E (Minor 3rd)
• G# (Perfect 5th)
• B (Minor 7th)
• D# (Major 9th)

The presence of the low E (E2) provides a solid foundation, allowing the chord to be voiced as a C#m9 with an E in the bass. This arrangement makes it incredibly easy to achieve a rich, harmonically complex sound with minimal effort, opening up new possibilities for chord voicings and melodic ideas across the fretboard.

How to Tune Your Guitar to Open C#m9

To achieve the Open C#m9 tuning, you will adjust your strings from standard EADGBe tuning. Please note the semitone adjustments and be mindful of your string tension, especially for significant changes.

• 6th String (Low E): Keep as is; no change (0 semitones). Stays at E2.
• 5th String (A): Tune down 1 semitone to G#2.
• 4th String (D): Tune down 1 semitone to C#3.
• 3rd String (G): Tune down 3 semitones to E3. (Exercise caution when tuning down multiple semitones.)
• 2nd String (B): Keep as is; no change (0 semitones). Stays at B3.
• 1st String (High E): Tune down 1 semitone to D#4.

For any string that requires tuning down 4 or more semitones, or tuning up 4 or more semitones, it's generally advisable to consider using a different string gauge to avoid undue tension or slackness.

Here are the specific notes for each string in the Open C#m9 tuning:

• String 6: E2 (Low E)
• String 5: G3# (G sharp)
• String 4: C4# (C sharp)
• String 3: E3 (E)
• String 2: B3 (B)
• String 1: D5# (D sharp)