The Open Cmaj7 tuning transforms your Guitar into a resonant canvas, immediately delivering a rich C major seventh chord when all strings are strummed open. This creates a full, warm, and slightly jazzy or ethereal sound, perfect for ambient textures, fingerstyle, or powerful strumming. As the original description notes, this is a mixed tuning that may require a combination of string gauges, lighter on top and heavier on bottom, to optimize feel and tension. If you experience neck bowing, remember that the truss rod is designed to counteract string tension and can be adjusted accordingly.

Technical Analysis:

This tuning sets the open strings to C-G-C-G-B-E (low to high). These notes collectively form a C major seventh chord (C, E, G, B), making it an authentic open Cmaj7 tuning. The repetition of C and G across different octaves provides a powerful, fundamental resonance. The G-B-E on the top three strings maintains the standard G-B-E interval, which means many familiar chord shapes and arpeggios on those strings will remain accessible or easily adaptable. The lower strings (C-G-C) provide a deep and solid foundation. This tuning is excellent for achieving drone effects and is highly conducive to slide guitar, as a single barre across any fret will produce a major seventh chord.

How to Tune:

• 6th String (Low E): Tune down 4 semitones from E2 to C2. (Note: Tuning down 4 semitones is a significant drop; ensure your string gauge can handle this tension change, and exercise caution.)
• 5th String (A): Tune down 2 semitones from A2 to G2.
• 4th String (D): Tune down 2 semitones from D3 to C3.
• 3rd String (G): Keep as is; no change from G3.
• 2nd String (B): Keep as is; no change from B3.
• 1st String (High E): Keep as is; no change from E4.

6th String: C2

5th String: G2

4th String: C3

3rd String: G3

2nd String: B3

1st String: E4