Tuning Description: Open Cmaj13

Verbal Analysis: This unique "Open Cmaj13" tuning, as described by its creator, transforms your guitar into a rich, resonant chord when strummed open, perfect for creating lush soundscapes and expansive harmonies. A defining characteristic, noted by the creator, is the close interval between the top two strings (B3 and C4), just a semitone apart. This creates a fascinating tension and subtle dissonance that adds a modern, almost jazz-like complexity to the overall C major tonality, preventing it from sounding overly sweet. It's a tuning that invites experimentation, offering a full, extended major chord sound that can be easily modulated up and down the fretboard with simple barre shapes, while also providing intriguing harmonic possibilities for single-note lines and arpeggios due to its unique internal intervals.

Technical Analysis: The open strings are tuned to C2-A2-C3-E3-B3-C4 (from low to high). This arrangement presents a C major chord (C-E-G-B) with the G omitted, and includes the 6th (A) and 7th (B) – thus forming a Cmaj7(add6) or C6/7 voicing, commonly referred to as a Cmaj13 due to the presence of the 6th/13th. The string intervals are:

• Low C2 to A2: Major 6th
• A2 to C3: minor 3rd
• C3 to E3: Major 3rd
• E3 to B3: Perfect 5th
• B3 to C4: minor 2nd (semitone)

Chordal Opportunities:

• Strumming the open strings immediately yields a rich Cmaj13 chord.
• Barring across any fret will easily produce other major 13th voicings (e.g., barring at the 3rd fret gives an Ebmaj13).
• The close proximity of E3, B3, and C4 allows for interesting clusters and arpeggiated figures that highlight the major 7th and the unique semitone interval.
• The open C and A strings provide a solid bass foundation for folk, blues, or experimental playing, while the higher strings offer complex harmonic color.

How to Tune Your Guitar to Open Cmaj13

To achieve the Open Cmaj13 tuning from standard E-A-D-G-B-E, follow these steps. Please note that significant changes in string tension (tuning down 4 semitones for some strings) may require thicker gauge strings for optimal playability and intonation. Generally, tuning up or down more than 4 semitones is advised with a different gauge string. Always tune carefully and be mindful of your instrument's capabilities.

• String 6 (Low E String): Tune down 4 semitones from E2 to C2.
• String 5 (A String): Keep as is; no change (0 semitones) from A2 to A2.
• String 4 (D String): Tune down 2 semitones from D3 to C3.
• String 3 (G String): Tune down 3 semitones from G3 to E3.
• String 2 (B String): Keep as is; no change (0 semitones) from B3 to B3.
• String 1 (High E String): Tune down 4 semitones from E4 to C4.

Remember to always tune carefully, especially when making significant changes to string tension.

Open String Notes (Low to High):

• String 6: C2 (Low C)
• String 5: A2 (A)
• String 4: C3 (Middle C)
• String 3: E3 (E)
• String 2: B3 (B)
• String 1: C4 (High C)