Power chords are one of the easiest and most frequently used tools when writing rock/metal riffs, serving as flexible shapes which can be moved up and down the neck to alter its key.
One unique property of power chords is their lack of major or minor qualities due to a missing third note; this gives them a sort of “chameleon-like” quality that allows for seamless compositions.
1. Root-fifth chords
Root-fifth chords are an easy and flexible power chord formation made up of only the root and fifth notes. Root-fifths make an excellent starting point as their fingering pattern for A major bar chord can easily move up and down fretboard.
Root-fifth chords typically sound similar to triads when played in their first inversion (i.e., using E as its lowest note as its root note). However, these chords can also be seen as stacks of fourths or fifths; when this method is employed the fifth note becomes the bass note.
Practice both ways of playing these chords so that you can gain an understanding of their effects within other forms of music, for instance listening to rock songs which use root-5th chords and writing basslines that incorporate them.
2. Major seventh chords
These chords are among the first types of seventh chords you’ll come across in music and are excellent for creating tension within progressions. Constructed using major triads but flattening out their fifth by one semitone so that between their fourth and seventh is an interval that forms a minor 7th (C – Eb – G).
They’re sometimes known as half-diminished chords and often added to dominant function chords such as VV and viivii, although you might also encounter them in chords of predominant function like iiiii and, to an extent, IVIV.
Reduced chords are written using lowercase M and number 7 or just min7 in shorthand to differentiate them from other diminished chords. They’re simple to create; all it takes is stacking a minor triad with an Eb on top of a major triad with minor 7th (C-C-Eb). That’s it!
3. Major ninth chords
Jonny and I love using 9th chords because they add so much musical color to chords you already know! Just be wary not to overuse them as 9ths have very rich harmonic content which may result in muddy sounds if overdriven.
Build a major ninth chord by adding nine to any dominant seventh or minor seventh chord (even minor seventh!). Or you could use an open chord and add sus 2 notes which, technically speaking, also count as nines – these chords tend to sound jazzier than their regular open counterparts and make for an ideal ending chord when played after regular open chords for extra-finesse sounding endings.
Listen to Debussy’s breathtaking climax in his classic piece “Dance for a Dead Princess.” He builds up the music with beautiful chords that gradually move down before returning up again at bar 26 – culminating with a gorgeous minor ninth chord with deep low tones and an octave above it – blending perfectly with the dominant seventh that came before it.
4. Minor seventh chords
The major seventh power chord can be found throughout contemporary and romantic music alike; Debussy used this chord famously in “Claire de Lune.” To make this chord minor, simply remove its third from its top triad.
Create a minor power chord by adding the diminished seventh interval at the top of a triad. This results in a chord that sounds similar to a minor seventh but with richer harmonic texture and slightly different character.
This chord extension works with any of the four power chord shapes and is easy to play on most string sets. Although switching back and forth between an extended power chord shape and its original power chord shape may take practice, its expressive benefits make the effort worth your while!