The Brazilian Cmaj7(6/9) Open Tuning transforms your guitar into a vibrant and rich sonic landscape, deeply rooted in the Brazilian musical tradition. This exquisite tuning instantly delivers a full, open C major 7th chord with added 6th and 9th extensions, making it perfect for bossa nova, samba, jazz, and sophisticated pop. Its inherent harmonic density means that even simple strumming reveals complex voicings, while allowing for effortless melody playing over a lush harmonic bed. It's a tuning that encourages lyrical phrasing and a deep, resonant tone.

Technical Analysis

Technically, the open strings are tuned to C2-G2-B2-E3-A3-D4. This arrangement provides a complete Cmaj7(6/9) chord (C-E-G-B-A-D) right from the open strings, with C (root) on the 6th string, G (5th) on the 5th, B (major 7th) on the 4th, E (major 3rd) on the 3rd, A (6th) on the 2nd, and D (9th) on the 1st string. The intelligent voicing with the root and fifth in the bass provides a strong foundation.

Many common chord shapes become immediately accessible:

• Open Chord: A glorious Cmaj7(6/9) itself, resonant and full.
• Barre Chords: By simply barring across various frets, you can transpose this powerful chord shape, making it easy to play other maj7(6/9) chords up and down the neck. For instance, barring at the 2nd fret would yield a Dmaj7(6/9).
• Partial Chords: The top three strings (E3-A3-D4) form an E-minor chord with an added A and D, or an A-sus2 shape (A-D-E). The middle four strings (G2-B2-E3-A3) present an inversion of a Cmaj7 or related harmony, opening up unique melodic and harmonic possibilities.

The strong intervallic relationships (e.g., perfect fifth between C2 and G2, major third between G2 and B2, perfect fourth between E3 and A3) ensure both consonance and musical interest, ideal for intricate fingerstyle or rhythmic strumming.

How to Tune

To achieve the Brazilian Cmaj7(6/9) Open Tuning from standard EADGBe tuning, follow these specific adjustments for each string:

• String 6 (Low E to C2): Tune down 4 semitones. This is a significant drop from E2 to C2, so ensure your string tension remains stable.
• String 5 (A to G2): Tune down 2 semitones from A2 to G2.
• String 4 (D to B2): Tune down 3 semitones from D3 to B2.
• String 3 (G to E3): Tune down 3 semitones from G3 to E3.
• String 2 (B to A3): Tune down 2 semitones from B3 to A3.
• String 1 (High E to D4): Tune down 2 semitones from E4 to D4.

Important Considerations:
Please note that several strings involve tuning down by 3 or 4 semitones. While generally manageable, for extreme or prolonged use of this tuning, especially for the 6th string's 4-semitone drop, you might consider a heavier gauge string to maintain optimal tension and tone. Always tune carefully and gradually to avoid string breakage or damage to your instrument.