The C7Sus4 tuning for Guitar is a uniquely deep and resonant configuration, establishing a C7sus4 chord (C-G-C-F-A#-C) right from its open strings. This tuning delves into lower registers, particularly with the 6th string tuned down to C2, offering a rich, bass-heavy foundation.

Verbal Analysis

This tuning creates an immediate sense of tension and resolution with its dominant suspended quality. The open C7sus4 chord is full and powerful, lending itself well to blues, jazz fusion, and contemporary rock styles where a strong, open-string drone is desired. The lower register C on the 6th string provides a deep root, while the subsequent perfect fourths and fifths build a harmonic landscape that is both familiar and exotic. Players will find this tuning inspiring for riffs and arpeggios that leverage the open chord, creating a unique sonic texture. The unusual arrangement of the first two strings, with the 2nd string (A#4) being pitched higher than the 1st string (C4), will introduce a significant challenge and a new approach to lead playing and chord voicings, forcing players to rethink traditional scale and arpeggio patterns.

Technical Analysis

The tuning consists of the following notes from low to high:

• String 6: C2
• String 5: G2
• String 4: C3
• String 3: F3
• String 2: A#4
• String 1: C4

Analyzing the intervals between adjacent strings:

• String 6 (C2) to String 5 (G2): Perfect Fifth (7 semitones)
• String 5 (G2) to String 4 (C3): Perfect Fourth (5 semitones)
• String 4 (C3) to String 3 (F3): Perfect Fourth (5 semitones)
• String 3 (F3) to String 2 (A#4): This is a significantly wide interval of 16 semitones (an augmented third plus an octave). This large jump may require careful string selection for the 2nd string to withstand the tension, or a lighter gauge to prevent snapping.
• String 2 (A#4) to String 1 (C4): This is a highly unusual descending interval where the 1st string (C4) is pitched 9 semitones lower than the 2nd string (A#4). This inverted string order for the highest strings will fundamentally alter chord shapes and lead lines, demanding a complete re-learning of typical guitar fingerboard logic.

The open strings collectively form a C7sus4 chord (C-G-C-F-A#-C). This makes it ideal for drone-based compositions or for quick, powerful rhythmic strumming. Chords built on the open C7sus4 root can be easily formed by barring frets, yielding other 7sus4 voicings (e.g., barring the 1st fret gives C#7sus4). Due to the consistent Perfect 4th intervals on strings 5-3, many common chord shapes will need to be re-imagined or simplified, with potential for unique open voicings.

How to Tune to C7Sus4

To achieve this tuning, begin from standard EADGBe tuning. Carefully adjust each string as follows:

• 6th String (Low E): Tune down 4 semitones from E2 to C2.
• 5th String (A): Tune down 2 semitones from A2 to G2.
• 4th String (D): Tune down 2 semitones from D3 to C3.
• 3rd String (G): Tune down 2 semitones from G3 to F3.
• 2nd String (B): Tune down 1 semitone from B3 to A#3.
• 1st String (High E): Tune down 4 semitones from E4 to C4.

Important Note on String 2: There is a discrepancy between the target note for the 2nd string (A#4) specified in the tuning details and the tuning instruction (tune down 1 semitone from B3). Tuning B3 down 1 semitone results in A#3, not A#4. Achieving A#4 from B3 would require tuning up a significant 11 semitones. This drastic change in pitch (tuning up 11 semitones or the intended A#4 resulting in the 2nd string being higher than the 1st string) may necessitate a different string gauge to prevent string breakage or damage to your instrument. Please verify the intended pitch for the 2nd string (A#3 or A#4) before proceeding, and exercise extreme caution if attempting to reach A#4 from B3. The description above for the tuning's musical characteristics is based on the target notes as provided, including A#4 for the 2nd string.

As several strings are tuned down by 4 or more semitones (String 6 and String 1), consider using a heavier gauge string set if you intend to keep your guitar in this tuning for extended periods, especially for the lower strings, to maintain adequate tension and tone. Conversely, reaching A#4 on the 2nd string (if that is the true intent) would likely require a very light gauge string and extreme caution.