The Mauna Loa tuning, a delightful and resonant open C6 tuning, originates from the rich tradition of Hawaiian Slack-Key guitar. This tuning is not just a collection of notes; it's an invitation to explore warm, lush harmonies and melodies characteristic of its heritage. Known for its 'slack' or loosened strings, it provides a distinctive, mellow voice to the instrument, ideal for fingerstyle playing and creating a strong sense of place and mood.

Technical Analysis:

The open strings are tuned to C2-G2-E3-G3-A3-E4, which creates a beautiful C6 chord when strummed openly. Let's break down its harmonic structure:

• The lowest three strings (C2-G2-E3) form an inverted C major triad (root, fifth, third), providing a strong harmonic foundation with a deep, resonant bass.
• The presence of both C and E notes in the low and high registers (C2, E3, E4) creates a full and vibrant major tonality, allowing for a wide spread of the fundamental chord.
• The repeated G notes (G2 on the 5th string and G3 on the 3rd string) reinforce the dominant fifth of the C chord, adding to the tuning's stability and rich resonance.
• The A3 on the second string is the crucial element that introduces the sixth, transforming the open major triad into a rich and mellow C6 chord. This C6 voicing is particularly sweet and characteristic of Hawaiian music, ideal for gentle strumming and intricate fingerstyle compositions.

This open C6 chord allows for immediate, full-bodied harmonies with minimal effort. Players can easily create drone effects and melodic lines over the sustained C6. While standard chord shapes will be significantly altered, barres across various frets will transpose the open C6 chord, yielding other 6th chords (e.g., F6 at the 5th fret, G6 at the 7th fret). The specific intervalic structure (Root-5th-3rd-5th-6th-3rd relative to C) provides a distinctly open and harmonically rich canvas, inviting experimentation with single-finger slides and partial barres to discover a wealth of new voicings and melodic possibilities unique to this tuning.

Open String Notes:

• String 6 (Lowest E): C2
• String 5 (A): G2
• String 4 (D): E3
• String 3 (G): G3
• String 2 (B): A3
• String 1 (Highest E): E4

How to Tune (from Standard E-A-D-G-B-E Tuning):

• String 6 (Low E): Tune down 4 semitones to C2. (Note: Tuning down 4 semitones is a significant change. If you plan to keep your guitar in this tuning for extended periods, consider a heavier gauge string for optimal tension and tone stability.)
• String 5 (A): Tune down 2 semitones to G2.
• String 4 (D): Tune up 2 semitones to E3.
• String 3 (G): Keep as is; no change (0 semitones) to G3.
• String 2 (B): Tune down 2 semitones to A3.
• String 1 (High E): Keep as is; no change (0 semitones) to E4.