The C7 Blues Tuning by Papa Dafoe

This unique C7 tuning, attributed to Papa Dafoe, is specifically designed for a rich blues sound, particularly effective on lap steel. It transforms your standard guitar into an open C7 dominant chord, making it an excellent choice for slide guitarists and blues enthusiasts looking for a distinctive voice.

Technical Analysis: Open Chord Voicing

The open strings of this tuning are presented as C2, G2, C3, G3, A#4, E4. Analysing these notes reveals a powerful C7 chord:

• C (Root): Provided by the 6th and 4th strings, establishing a strong fundamental.
• G (Perfect 5th): Present on the 5th and 3rd strings, reinforcing the harmonic foundation.
• E (Major 3rd): Found on the 1st string, giving the chord its major quality.
• A# (Minor 7th): On the 2nd string (enharmonically equivalent to Bb), providing the crucial dominant 7th character essential for blues.

The full open voicing is C-G-C-G-A#-E. This arrangement offers a wide, resonant C7 chord, perfect for open strumming or slide work. The lower strings provide a solid C power chord base, while the higher strings add the major third and minor seventh, creating a classic dominant blues sound.

Chords and Playability

With the open strings forming a C7 chord, you can immediately play a C7 by simply strumming all open strings. This makes it incredibly intuitive for blues progressions. By barring across a single fret, you can effortlessly access other dominant 7th chords. For instance, barring at the 5th fret will yield an F7 chord, and at the 7th fret, a G7 chord, making I-IV-V blues progressions very fluid and easy to execute with a slide.

The tuning's structure also lends itself well to single-note blues licks and fills, allowing for melodic improvisation over the dominant chord. The wide intervals and spread of the notes provide a unique harmonic texture that truly shines in a blues context, especially on lap steel.

How to Tune

To achieve this distinctive C7 tuning, follow these precise string adjustments from standard EADGBe tuning:

• String 6 (Low E): Tune down 4 semitones to C2. This is a significant drop from E.
• String 5 (A): Tune down 2 semitones to G2.
• String 4 (D): Tune down 2 semitones to C3.
• String 3 (G): Keep as is; no change (0 semitones) at G3.
• String 2 (B): Tune down 1 semitone to A#4 (often notated as Bb4).
• String 1 (High E): Keep as is; no change (0 semitones) at E4.

Important Note on String Tension: Tuning the 6th string down 4 semitones to C2 represents a considerable decrease in tension. While manageable for occasional use, if you plan to keep your guitar in this tuning for extended periods, or for a more stable and resonant tone, it is advisable to consider using a heavier gauge string for the 6th string. Generally, movements exceeding 4 semitones (either up or down) suggest that a different string gauge might be beneficial for optimal playability and string longevity.