The major 6th chord adds the 6th to a major triad (1–3–5–6). Warm and vintage, it softens a plain major and is a jazz and swing favourite.
NotesE · G♯ · B · C♯
Formula1 · 3 · 5 · 6
Every major 6th chord tone across the neck. Solo with these and you spell the chord — that's the difference between running a scale and playing the changes.