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Quartal Chord Voicings on Bass Guitar – Bass Practice Diary 45

Quartal Chord Voicings on Bass Guitar – Bass Practice Diary – 26th February 2019

I haven’t done a video about bass chord voicings for a while. So, this week I’ve decided to practice some of my favourite jazz chords, quartal chord voicings. Quartal harmony is a jazz term which means harmonising chords in intervals of a fourth.

4th Intervals

I did a video recently about playing modern jazz lines using 4th intervals. But I thought after making that video that I wasn’t telling the full story about using 4ths in modern jazz. The quartal chord voicings themselves create a very distinctive modern jazz sound. It’s instantly recognisable once you become familiar with the sound.

Chords are traditionally voiced in intervals of a third. Using quartal voicings in jazz became popular in the 1960’s after Miles Davis made quartal chord voicings a feature of his composition So What from the 1959 album Kind of Blue.

Quartal harmony was a sound that then became associated with the great John Coltrane Quartet of the early to mid 1960’s. The chords were supplied by pianist McCoy Tyner, who is synonymous with quartal harmony, and one of my all time favourite jazz pianists.

McCoy Tyner was using these voicings at a time when the Coltrane Quartet was playing a lot of modal jazz. Meaning that there weren’t lots of chord changes. And the emphasis was more on scalic improvisation over static harmony. So What is also a modal jazz piece. So, if you’re looking to apply some of these quartal chord voicings, then modal jazz tunes are a good place to start.

Quartal Harmony on Bass

The bass is setup for playing quartal chord voicings because the strings are tuned in intervals of a fourth. Which is why it amazes me that more bass players don’t use quartal chord voicings. Many of the chord voicings in the video can be played with just one finger. But despite this simplicity, they create a sophisticated jazz harmony sound.

Here is an A major scale harmonised in 4ths.

A major scale - quartal chord voicings
A major scale – quartal chord voicings

In the video, I’ve used the open A string as a root note underneath all of these voicings.

When you play this, it doesn’t sound like a typical major scale harmonisation. That’s what’s so great about quartal harmony. You can take simple harmony, like a major scale, and completely change it’s character, without needing to change or add any notes.

It works for all of the modes of the major scale. Here is the Dorian mode harmonised in 4ths.

A dorian - quartal chord voicings
A dorian – quartal chord voicings

Applying Quartal Harmony to Jazz

I’ve already mentioned that quartal chord voicings are extremely well suited to modal jazz. If, for example, you’re playing a modal jazz composition with long periods on a minor seventh chord. Like So What or John Coltrane’s Impressions. Then you’re faced with a challenge of how to make just one chord sound interesting.

One solution would be to apply the dorian chord voicings that I’ve written out in the example above. It gives you seven different options for voicings that you could play over a single minor seventh chord (Am7 in the example above). You could use any or all of these voicings to help create a feeling of movement in the otherwise static harmony.

You can apply quartal harmony to virtually any scale or mode. In this next example I’ve applied it to an A harmonic minor scale.

A harmonic minor - quartal chord voicings
A harmonic minor – quartal chord voicings

The same chord voicings can also be applied to any of the modes of the harmonic minor scale, which includes the altered scale.

One of the fourth intervals in the harmonic minor scale actually comes out as a major third. So, some of the voicings in the example above are not strictly quartal. Because they mix fourths with a third. But it still creates some interesting sounds and you can do your own experimenting to decide which of the voicings are useful.