The traditional power chord contains a perfect fifth. Turning it up side down changes its sound slightly.
Guest Post from Songwriting: Get Your Black Belt In Music & Lyrics
A Meaner and Tighter Power Chord Sound
Taking the top note of a power chord and lowering it an octave places it a perfect fourth underneath the root note. This new voicing of the chord is often referred to as an inverted power chord. As described in the tip A Good Old Hard Rock Trick it can be used in combination with the standard power chord, but you might also want to try doing the guitar arranging solely with the inverted chord.
Fifths and fourths are related intervals, the inversion of a fifth is a fourth. Not surprisingly, they sound quite similar, but there is a slight difference. The notes of the inverted version sits a bit closer to each other. A common opinion is that the inverted power chord sounds a bit meaner. You can hear it in the iconic intro riff of the song Smoke on the Water by Ritchie Blackmore, Ian Gillan, Roger Glover, Jon Lord and Ian Paice (Deep Purple).
Having the root notes of your chords at the bottom of the arrangement/music production is often important, because you want the chord progression to be easily understood. When you’re playing inverted chords this is not happening, if we consider the guitar arrangement, but chances are that you also have a bass part. The bass will take care of the root notes!
Hey! If you’re playing an inverted chord on the low e-string and the a-string you might also want to try adding a second perfect fourth an octave above. These notes, you’ll be playing two frets up on the d-string and the g-string. It’s a really fat voicing!
Read more about power chords and get practical music production tips in the book: Songwriting: Get Your Black Belt In Music & Lyrics.