This week’s backing track has an interesting twist. The song can easily be played in the key of D, but the chords being used are 5 chords, which means they contain no major or minor 3rds in the harmony. The chords for the first section of the song are: E5-D5-A5. This allows you to play in E Dorian (key of D) or E Mixolydian (key of A). The chords for the second section are: G5-D5-A5. This progression allows you to play in G Lydian (key of D) or G major. It is this variety of scales that make playing over power chords, chords with no 3rds, so much fun.