The C Lydian Open Tuning is a wonderfully rich and evocative open tuning for the guitar, perfectly suited for exploring bright, dreamy, and sometimes melancholic soundscapes. As its name suggests, it heavily leans into the Lydian mode's characteristic raised fourth, offering a unique harmonic palette. It's described as being "good for lydian and dorian sounding songs, licks, and chord progressions," a testament to its versatility.

Technically, the open strings form a complex and beautiful chord: C2-G2-C3-A3-E4-F5#. This can be identified as a Cmaj6(#11) chord, or Cmaj6(add#4). The prominent C-G-C on the lowest strings provides a strong, resonant foundation, making power chords and low-end riffs particularly beefy. The addition of the A (a major 6th) and the E (major 3rd) builds a full C major 6th chord. The crowning jewel is the F# (a raised 4th or #11) on the highest string, which instantly injects the bright, ethereal quality of the Lydian mode into your playing.

With this tuning, open strumming produces a lush, sophisticated sound that immediately suggests compositional possibilities. Simple two-finger chords or single-string melodies can take on unexpected harmonic depth due to the resonant open strings. For instance, barring across a fret will yield various Lydian or major-sounding voicings. The lower three strings (C-G-C) are perfect for powerful drones or easy open C power chords. The interval between the 3rd (A) and 2nd (E) string is a perfect fifth, opening up easy minor or major triad shapes on those strings. Exploring melodies against the open Cmaj6(#11) chord will naturally lead to Lydian ideas, while minor key concepts can still find a home, particularly with the G and A notes providing a comfortable Dorian flavor. Experiment with movable shapes up the neck, focusing on chord tones that highlight the Lydian #4 for that signature bright sound.

How to Tune to C Lydian Open Tuning

To achieve the C Lydian Open Tuning, start from standard EADGBe tuning and make the following adjustments. Please pay close attention to the semitone movements, especially for larger changes. Tuning up significantly can put extra tension on your strings and neck, while tuning down excessively might make strings feel too loose.

• String 6 (Low E): Tune down 4 semitones (2 whole steps) from E2 to C2. Caution: This is a significant drop. Consider a heavier gauge string for optimal tone and tension if you plan to keep this tuning for extended periods.
• String 5 (A): Tune down 2 semitones (1 whole step) from A2 to G2.
• String 4 (D): Tune down 2 semitones (1 whole step) from D3 to C3.
• String 3 (G): Tune up 2 semitones (1 whole step) from G3 to A3.
• String 2 (B): Tune up 5 semitones (2 and a half steps) from B3 to E4. Caution: This is a substantial increase in tension. Consider a lighter gauge string if this tuning causes undue stress on your guitar or feels too tight.
• String 1 (High E): Tune up 2 semitones (1 whole step) from E4 to F#4. Important Note: While this movement from standard E results in F#4, the specified tuning note for this string is F5# (an octave higher). Achieving F5# from E4 would require tuning up 14 semitones (7 whole steps), which is an extreme tension increase and strongly advises using a significantly lighter gauge string or a dedicated high-octave string set to avoid string breakage and potential guitar damage. The provided movement of +2 semitones is specifically for F#4.

String Gauge Recommendation

Given the significant tuning changes, especially for String 6 (down 4 semitones) and String 2 (up 5 semitones), and the potential for String 1 to be an octave higher than implied by its movement, adjusting your string gauges is highly recommended for optimal playability, tone, and guitar health. For the lower strings, a heavier gauge might compensate for the slack, while for the higher strings with large upward movements, lighter gauges would prevent excessive tension and breakage. For String 1, if aiming for F5#, a very light gauge or a custom string set is essential.