This unique tuning, known as Thorn Birds Al Petteway CADGAD, is a captivating modification of the popular DADGAD tuning, designed to evoke the specific mood of Al Petteway's 'The Thorn Birds' theme. It's particularly well-suited for fingerstyle playing and creating rich, atmospheric soundscapes. The deep C on the lowest string provides a strong, earthy foundation, while the open A, D, G, A, D strings above it offer a shimmering harmonic palette. This configuration facilitates a smooth key change from C to D, as indicated in its original description, allowing for versatile melodic and harmonic exploration.

Technical Analysis

The open strings for this tuning are C2-A2-D3-G3-A3-D4. Compared to standard EADGBe tuning, this setup presents a significantly altered harmonic landscape. Let's look at the intervals between the open strings:

• 6th String (C2) to 5th String (A2): A Major 6th up.
• 5th String (A2) to 4th String (D3): A Perfect 4th up.
• 4th String (D3) to 3rd String (G3): A Perfect 4th up.
• 3rd String (G3) to 2nd String (A3): A Major 2nd up.
• 2nd String (A3) to 1st String (D4): A Perfect 4th up.

The repeated perfect fourths (A-D, D-G, A-D) provide strong harmonic resonance and ease of movement across the fretboard, while the major second (G-A) offers a melodic leading tone. The open strings C, D, G, A collectively suggest a Dsus2/C tonality or a Gsus4 with added C and A, offering a rich, open voicings that are neither purely major nor minor, but highly evocative.

Chords and Playability

The open string combination (C-A-D-G-A-D) itself can be strummed to create a full, resonant chord with a distinct character. Due to the spacing:

• Open Chords: The presence of C, G, D, and A notes across the open strings makes various C, G, and D-family chords easily accessible with minimal fretting. For instance, an open C major chord (C-E-G) can be approximated with the C and G, and a D major chord (D-F#-A) is supported by the D and A.
• Drone Potential: The repeated D and A notes provide excellent opportunities for creating sustained drones, adding depth to melodies played on other strings.
• Power Chords: Forming power chords on the lower strings (e.g., C5 on the 6th string, D5 on the 4th string) is straightforward, providing powerful rhythmic foundations.
• Modal Playing: The open D, G, A notes are conducive to exploring D-centric modes, such as D Mixolydian or D Dorian, which will sound particularly lush and open.
• Fingering Efficiency: Many common chord shapes will need to be re-learned, but new, often simpler, fingerings for complex voicings emerge, especially for diatonic chords in C or D.

How to Tune

To achieve the Thorn Birds Al Petteway CADGAD tuning from standard EADGBe, follow these steps:

• 6th String (Low E): Tune down 4 semitones from E2 to C2. Important: Tuning down 4 semitones is a significant change in string tension. If your guitar shows signs of intonation issues or difficulty holding tension, consider using a heavier gauge string for optimal performance at this low C.
• 5th String (A): Keep as is; no change (A2).
• 4th String (D): Keep as is; no change (D3).
• 3rd String (G): Keep as is; no change (G3).
• 2nd String (B): Tune down 2 semitones from B3 to A3.
• 1st String (High E): Tune down 2 semitones from E4 to D4.