What chords are in B Mixolydian?
Chord identification The B mixolydian chord I is the B major chord, and contains the notes B, D#, and F#. This tonic chord’s root / starting note is the 1st note (or scale degree) of the B mixolydian mode. The roman numeral for number 1 is ‘I’ and is used to indicate this is the 1st triad chord in the mode.