Tuning Analysis: A7 sus2

The A7 sus2 tuning is a powerful and unique alternative tuning, famously employed in songs like 'AAA', 'Kingdom' from Physicist, and 'Centipede'. It creates a massive, resonant sound due to its low, repeated root notes, making it ideal for heavy, driving riffs and atmospheric textures.

Technical Breakdown

This tuning transforms the standard E A D G B E configuration into A A A G B E. Let's break down the intervals relative to the root (A):

• String 6 (Low A1): The fundamental root note, an octave below standard A2. This creates a deep, foundational tone.
• String 5 (A2): An octave of the root, reinforcing the fundamental.
• String 4 (A2): Another octave of the root, further thickening the low end and creating a massive, almost symphonic drone when strummed open.
• String 3 (G3): A minor seventh above the root A. This provides the '7' quality, giving the tuning its dominant/minor seven flavour.
• String 2 (B3): A major second above the root A. This note replaces the major or minor third, creating the 'sus2' (suspended second) quality, which is often perceived as open and airy, or slightly dissonant, depending on context.
• String 1 (E4): A perfect fifth above the root A. This provides harmonic stability and a clear anchor for the upper register.

The open strings collectively spell A, B, E, G, which is an an A sus2 chord (A, B, E) with an added minor seventh (G). This results in an A7 sus2 voicing. The repeated low A notes provide an incredible amount of girth and sustain, perfect for drop-tuned metal or atmospheric soundscapes.

Open Chords & Playability

The most immediate open chord is, of course, the A7 sus2 itself by strumming all six strings. The three low A strings allow for incredibly thick power chords by simply muting higher strings, or by barring across the low three strings at any fret to create powerful, octave-rich root notes. Due to the significant drops on the 6th and 4th strings (-7 and -5 semitones respectively), string tension on these strings will be considerably looser than standard. For optimal playability, intonation, and to avoid excessive string flop, especially for aggressive playing styles, a heavier gauge string set is strongly advised for strings 6 and 4.

How to Tune

• String 6 (Low E to A1): Tune down 7 semitones. This is a significant drop; a heavier gauge string is advised for better tension and tone.
• String 5 (A to A2): Keep as is; no change (0 semitones).
• String 4 (D to A2): Tune down 5 semitones. Another substantial drop; a heavier gauge string may be beneficial here too.
• String 3 (G to G3): Keep as is; no change (0 semitones).
• String 2 (B to B3): Keep as is; no change (0 semitones).
• String 1 (High E to E4): Keep as is; no change (0 semitones).