Thundercat Chord Theory

illustration of thundercat playing bass

By Dan Carr

This article originally appeared on Reverb Machine

+ Take your modern jazz piano and hip-hop beat making to new heights with Soundfly’s new course, Elijah Fox: Impressionist Piano & Production!

Thundercat is the stage name of Stephen Bruner, a bassist known for his work with Kendrick Lamar, Flying Lotus, Erykah Badu, and Suicidal Tendencies. He is also a successful solo artist with four albums under his belt, with 2016’s Drunk and 2020’s It Is What It Is garnering critical acclaim for their mixture of virtuosic bass-playing, guest appearances, and idiosyncratic humour.

Thundercat is heavily inspired by jazz musicians, citing Ron Carter, Herbie Hancock, Mary Lou Williams, and Miles Davis as the artists he introduced Kendrick Lamar to while collaborating on To Pimp a Butterfly. While he combines these jazz influences with funk, pop & R&B to create his eclectic sound, his jazz background has the strongest effect on how he approaches songwriting, with unusual harmonic chord progressions being one of the hallmarks of his sound.

He is also a fan of simple, catchy melodies which he masterfully combines with these jazzy, “outside” chord progressions.

Thundercat Music Theory

Although Thundercat is mostly famous for his Moogerfooger-processed bass sound (sometimes mistaken for a bass synth), in this article I’m going to focus entirely on his songwriting. I’ve transcribed the chords and melody of five Thundercat songs to analyze music theory concepts used that you can also use in your own songwriting.

Out of all the chord theory articles I’ve written, this one covers the most complex ideas, so if you haven’t already, check out some of my previous Chord Theory articles.

“Friend Zone”

“Friend Zone” is a relatively straightforward composition for Thundercat and it’s built around a two-chord progression. The chords are Dm9 | D♭maj7, though the Dm9 is replaced with a Dm7sus4 in the synth-arpeggiated verse sections. Dm9 and Dmaj7 don’t belong together in any key or scale so there is a shift in harmony when the chord changes.

Despite this, they work together nicely because they share two notes: F and C. The chord change sounds like this:

Care has to be taken when playing a melody or singing over chords that change keys because notes that work over the first chord might not work over the second chord. In the first part of the “Friend Zone” verse, Thundercat sings a D minor scale (D E F G A C) melody over the Dm chord.

However, he ends each phrase by landing on an A note over the D chord. A doesn’t belong to the D minor scale but is one of the notes in Dmaj7 so this helps bridge the two chords together nicely.

Later in the “Friend Zone” verse, Thundercat extends his singing phrases over the Dmaj7 chord. To make the melody work with the chords, Thundercat shifts the melody notes from the D minor scale that he sings over the Dm chord to the D major scale over the D chord. With the scale notes changed, the melody fits perfectly over the new chord. When the chord changes back to Dm, the scale notes shift back to D minor.

Constantly changing scales like this might seem complicated, but a fundamental part of jazz composition and performance is navigating over complex chord changes. With enough practice, it becomes second nature to improvise over key changes like this.

I’ve looked at similar chord progressions in Mac DeMarco’s “A Heart Like Hers” and Depeche Mode’s “Shake the Disease.”

“Them Changes”

“Them Changes” is either named after its complex chord changes or as a nod to the Buddy Miles album of the same name.

Thundercat’s signature multi-layered six-string bass plays over a drum beat sampled from The Isley Brothers’ “Footsteps in the Dark.” There are two bass parts, seventh chord arpeggios down the middle of the mix and heavy auto-wah bass notes in the sides of the mix. If you use the Utility audio effect in Ableton Live to split the mid and sides, you can listen to both bass parts individually.

The song is in E minor and features a chord progression that features a few chromatic chords before landing on the home E minor chord. The full chord sequence is C♭maj7 | Gm7 | A♭m7 | Fm7 | E♭m11. Note that the Cmaj7 is the same as Bmaj7, but is notated as a Cmaj7 because the song is the key of G / Em. Below you can hear what it sounds like.

Note that I’ve included both bass parts in my transcription but in the audio clip I’m only playing the higher part.

Analyzed with Roman numerals, the chords are VI, IIIm, IVm, IIm, Im. The chords that are diatonic are the Cmaj7, Am and Em11 chords. The Gm7 is the most ‘outside’ chromatic chord in the sequence, and it works because it chromatically shifts up a semitone to Am7, which is in-key. It’s a common jazz track to approach a chord chromatically from one step below (or above) as it adds chromatic tension with an easy way to resolve it.

In contrast, the vocal melody in “Them Changes” is simple and uses notes almost entirely from the E minor pentatonic scale. This keeps the melody catchy and easy to sing along with while still working over the jazzy outside chord progression underneath. He doesn’t adjust any of the notes to fit the outside Gm7 chord because it’s only a passing chord. It can be easy to overthink things when working with complex harmony, but here Thundercat shows us that the simple approach is often the best one.

This mixture of complex chords and simple melodies is one of Thundercat’s signature tricks. It’s easy enough to write weird chord sequences, but it’s a much harder task to come up with a catchy, simple melody over the top.

A brief aside…

We recently launched a video on our YouTube channel about the mysterious origins of the triangular symbol that has come to represent the major seventh on jazz charts. Theorists and curiosity-junkies, come one come all, and subscribe if you like that sorta thing!

“Lava Lamp”

“Lava Lamp” showcases Thundercat’s melodic side with layered harmonized singing. Again, you can hear the three-part harmony vocals more clearly by isolating the mid and sides of the mix as the vocals are alone in the sides of the mix. The chords are almost entirely diatonic but the loop ends with a particularly spicy secondary dominant chord which I’ll have a look at.

“Lava Lamp” is in the key of Bm, with a chord progression of Gmaj7 | Bm11 and the sequence ends with an F#7#5/E chord. Long chord names can look scary, but it’s telling us that it’s an F#7 chord with an altered note and a different bass note. The #5 means the fifth is sharped; the fifth of F#7 is C#, so it’s raised a semitone to D, which is sung in the “Lava Lamp” harmony vocals. The “/E” means that the bass note is an E, which makes it a slash chord.

Adding extensions like #5, 5, #9 and 9 are a great way to add a jazzy sound to dominant chords. You don’t need to worry about whether the extension notes fit within the song key, the idea is that the dominant chord should sound dissonant but be resolved by the chord following it.

For a full breakdown of the instruments and production of “Lava Lamp,” check out Noisechest’s “Lava Lamp” deconstruction!

“Dragonball Durag”

“Dragonball Durag” is from Thundercat’s latest album, 2020’s It Is What It Is. The song is similar to “Them Changes” in that it employs a catchy melody over jazzy chord changes and a grooving drum beat.

The first part of the chord sequence is Em7 | F#m7 | Gmaj7 | Asus4 | Bm7sus4. These are all diatonic chords in the key of D major and the bass line is simply ascending the D major scale starting from E. All of the guitar chords here are voiced in 5ths, for example, the first chord is a G5 power chord (G and D) played over an E bass note which creates an Emin7 chord (E, G and D).

The E7 chord at the end of bar 2 is a II7 chord used to create more tension at the end of a phrase. Note that dominant chords don’t have to resolve as a V – I, they can be used just to add tension.

The next part of the “Dragonball Durag” chord sequence is Gmaj7 | F#m7 | Em7 | A | Dmaj7. These are more diatonic chords in the key of D major and the sequence ends with a classic jazz IIm V I leading to the D chord. The section ends with C#m7♭5 | F#7 which is a IIm V leading to Bm, which is the relative minor of D major. Again, this is an unresolved dominant chord, thrown in for colour and tension.

The vocal melody to “Dragonball Durag” is almost entirely composed of notes from the D major pentatonic scale. Like “Them Changes,” the key is simplicity. Although there are a few outside chords, you don’t have to change scale notes if they’re only passing chords.

Some highlights of the melody are the harmonized notes at the end of bar 3. The harmony is in fourths, meaning the higher note is a fourth interval (5 semitones) above the lower note. This is a less common way to harmonize than the more popular thirds harmony. The sung notes are pretty colourful over the underlying chords, with the F# and B over the A chord to imply a jazz-favorite A major 6/9 chord and an E and A over the Dmaj7 chord to imply a colourful Dmaj9 sound.

The melody uses non-pentatonic notes in bar 4 to add some color over the C#m7♭5 chord. This is the main “outside” chord, so Thundercat throws in a G natural note from the regular old D major scale. This is the 5 interval of the C#m75 (C# E G B) so it helps accent the outside chord. It’s pretty likely that Thundercat added this interval by ear because it fits the chord so well.

“Rabbot Ho” & “DUI”

Finally, let’s look at “Rabbot Ho,” the Drunk album-opener which also reappears in “DUI,” the Drunk album-closer.

The opening melody of “Rabbot Ho” is built on a simple five-note pattern that is chromatically transposed a semitone lower in bar 2 and five semitones lower in bar 3. The melody is played over some particularly colourful extended chords that seem to defy traditional chord arrangement.

At a guess, it seems to have been written with the melody first, then a descending bass line and finally the chords written to fill in the blanks. Here’s the melody and chords together:

Though the melody is simple, the chords used to harmonize it are on the complex side. The first five chords are descending minor chords. The Gm13 in bar 2 is a very dramatic sounding chord but it works because the note played by the melody is E and E is the 13th interval of G.

Bar 2 ends with an Fm/M7 | E♭m/M7 sequence. These are minor/major 7 chords, four-note chords with a minor 3rd and a major 7th. These chords have an unusual sound and aren’t commonly used; in “Rabbot Ho,” they’re used as a substitute for regular major 7 chords. The melody note is the major seventh of the underlying chord and swapping the major 3rd with a minor 3rd adds a strange quality to the sound. As the first five chords are all minor, it helps fit the descending theme.

In bar 3, things get a little more normal, as we start with a D♭maj7 chord, the root/home chord which finally creates a sense of resolution. This doesn’t last long as it’s followed by a IIm – V – I to C♭. The ii chord in this IIm – V- I is D♭min7 so you get this nice harmonic shift from D♭ major to D♭ minor.

In bar 4, the I chord of the IIm-V-I sequence is played as a C♭sus2#11 chord. This chord features only the root, 2nd, #4th and 5th intervals. Because the #4 and 5th are a semitone apart it’s important to voice the #4 an octave higher than the 5th. #11 and voicing is something that Thundercat definitely spends time on, as he mentions it in an interview quote that I’ll include at the end of this article.

So what to take from this?

Well, the chords don’t make a great deal of sense when analyzed like this, but they do sound cool, especially when played with the melody. As long as the melody is good, and the chords fit harmonically with that melody, the chord sequence will work. To make the chords fit harmonically, they should contain the melody notes within the chord.

A great musical exercise is to try reharmonizing a melody you like. It can be any melody, the simpler the better. Write the melody out, disregard the original chord progression and then write your own chord progression behind it. Don’t worry about making the chords fit within a key, just focus on making sure the melody notes are contained within the chords.

If the melody note is F then the obvious choice is an F major chord, but you can get more interesting results by using an E♭maj9 chord (E♭ G D F), a B7#11 chord (B D# A F) or an A♭13 chord (A♭ C Gb F). As well as coming up with original sequences, this will also open you up to harmonic ideas you hadn’t thought about before. Try it!

Q: How do you find melodies over your chord changes? Do you come up with the melody first?

A: They go hand in hand. Sometimes, I’ll hear the changes first, and I’ll ask myself what I’m supposed to find inside the harmony. Every once in a while, I’ll be hearing a melody, and I’ll try to create the changes around it. It comes from different places, and I try not to be scared or put limitations on myself. I’ll try anything, even if I hear something I don’t like. I’ll go for it. There’s no wrong way.

Q: Dissonance is such an essential part of your sound.

A: I like to try to think naturally, even if something is completely dissonant. And there’s a way to convey dissonance: If you play a major #11 chord, for example, hitting the #11 at a higher frequency may freak someone out because it sounds so dissonant, but if you play it as a ♭5, it’s more comforting.

– Thundercat (Guitar World)

Hopefully this article has given some insight on how to approach complex jazz chord sequences in songwriting which you can use for inspiration in your own music!

Don’t stop here!

Continue learning with hundreds of lessons on songwriting, mixing, recording and production, composing, beat making, and more on Soundfly, with artist-led courses by KimbraCom TruiseJlinRyan Lott, and the acclaimed Kiefer: Keys, Chords, & Beats.

Join our Mailing List

We offer creative courses, articles, podcast episodes, and one-on-one mentorship for curious musicians. Stay up to date!


I’m Not Saying Aliens Wrote This “House of Cards” Cue, But…

We break down the super hip “fourthi-fifthiness” sounding interval leap in this downright gorgeous cue from the “House of Cards” score.


How to Play With Meaning in Your Songwriting

Moving your listener through a broken narrative is an art, and you can master it with just a few simple tricks. Read on, dear songwriters…


The Surprising Origins of the Bagel Bites Theme Music

An exhaustive history of the catchiest ad jingle of all time. It goes so much deeper than we could’ve ever imagined and we break it ALL down.