The Cmaj7 tuning transforms your guitar into a harmonious canvas, providing an immediate, rich, and sophisticated open C Major 7th chord. This tuning is a delight for players exploring jazz, blues, contemporary ballads, or any genre that benefits from lush, complex harmonies. It encourages new melodic and harmonic approaches, opening up creative possibilities that are not readily available in standard tuning.

Technical Analysis

• Interval Structure: The open strings are tuned to C3, E3, G3, B3. From the lowest note (C3), this creates a perfect C Major 7th chord: C (Root), E (Major Third), G (Perfect Fifth), and B (Major Seventh).
• String Intervals: The intervals between adjacent strings are:
  • String 4 (C3) to String 3 (E3): Major 3rd (4 semitones)
  • String 3 (E3) to String 2 (G3): Minor 3rd (3 semitones)
  • String 2 (G3) to String 1 (B3): Major 3rd (4 semitones)
• This unique interval pattern between strings facilitates interesting fingerings and provides a distinct harmonic flavor, making it easy to voice advanced chords.

Open Chords and Possibilities

• C Major 7th: The most obvious benefit is the open Cmaj7 chord, offering a full, resonant sound without any fretting.
• Barre Chords: By simply barring across all four tuned strings at any fret, you can easily play other Major 7th chords. For example, barring at the 2nd fret yields a Dmaj7, the 5th fret an Fmaj7, and the 7th fret a Gmaj7.
• Related Chords: Experiment with minor 7th chords by flattening the B string (String 1) by one semitone to a Bb, which would give you a C7 (dominant 7th) chord. With careful fretting, various inversions and extensions become accessible across the neck.

How to Tune

To achieve the Cmaj7 tuning, adjust your guitar strings as follows (assuming standard EADGBe tuning and referring to the corresponding strings):

• String 4 (D-string): Tune down 2 semitones to C3.
• String 3 (G-string): Tune down 3 semitones to E3.
• String 2 (B-string): Tune down 4 semitones to G3.
• String 1 (High E-string): Tune down 5 semitones to B3.

Important Note on String Gauge: Please take care when changing tunings. String 2 and String 1 require significant adjustments, being tuned down by 4 and 5 semitones respectively. When tuning down by more than 4 semitones (or up by more than 4 semitones), the original string gauge may result in a loss of tension, leading to floppiness or intonation issues. For optimal playability and stability in this tuning, a heavier gauge string is advised for these particular strings if you plan to use this tuning frequently.

String 4: C3 (Lowest pitched string in this tuning)
String 3: E3
String 2: G3
String 1: B3 (Highest pitched string in this tuning)