Steely Dan: The Mu Major Chord

Just what is the mysterious Steely Dan mu (µ) major chord?

Mu major Part 1 Mu major Part 2 Mu major Part 3

New: The Birth of the Mu Major chord

Read my article "The Birth of the Mu Major Chord" which describes the first documented use of the chord in 12th century Paris (article hosted on Mizar6 website).


The Mu Major Chord - Part 1


The mu major chord is something musicically inclined Steely Dan fans have often asked themselves about. Just what is the chord? What does it sound like? Which songs use it?

The chord, or rather the name mu major, was invented by Donald Fagen and Walter Becker, quite possibly while sitting at the piano working on their early demos in the late 60s/early 70s. From the early days of Steely Dan it quickly became a favourite chord of theirs and, along with a small number of other favoured chords, is one of the defining characteristics of Steely Dan harmony.

The mu major chord features, in various forms, in songs on all Steely Dan albums. However, the chord is used not only in Steely Dan songs but in songs by many different artists, although others would probably know the chord by a different name. So the chord itself is not unique to Steely Dan - but the way Donald and Walter used the chord, the voicings they chose, and the chord changes they used it in made it something rather special in Steely Dan music.

What does the mu major chord sound like?

The best way to get used to the sound of the mu major chord is by playing the examples described below on a guitar or keyboard. But, for a quick introduction, have a listen to the file below which is a collage of mu major chords from various Steely Dan songs.

Mu major example: sound collage
MP3 file (253 K)

(128 Kbps)

Wav file (1.4 M)

(stereo, 16 bits, 22kHz)

Wav file (693 K)

(stereo, 16 bits, 11kHz)

What is the mu major chord?

As Donald Fagen has explained on occasions, the mu major chord is "a major chord with an added second". (Read the Compuserve chat where Donald talks about the mu major). In other words, the notes that make up the mu major chord are: Root (1st), 2nd, major 3rd, 5th.

Mu major = major triad + 2nd = 1st + 2nd + maj 3rd + 5th

The usual name for this chord is an add2 chord, sometimes also called an add9 chord. So where Steely Dan use the name "mu major" (or perhaps µ major) others might be more used to add2 or add9.

Note: if you're not sure of the differences between an add2 and a sus2 chord, or between an add9 and a 9 chord, you might want to brush up on a little chord theory.

Mu major examples:

  • In the key of G, the mu major chord has the notes: G A B D
  • In the key of E, the mu major chord has the notes: E F# G# B

... so is the mu major chord simply an add2 chord?

Yes and no ...
In terms of the notes used, there is no difference between a mu major chord and an "ordinary add2 chord". What marks out the Steely Dan mu major chord as something a little different is the way the chord is voiced and used. Using different voicings for the chord alters its sound, and there are some particular voicings that are used frequently in Steely Dan songs, giving a distinctive sound. Also, the harmonic context in which the chord is used affects the sound. The chord vocabulary used by Steely Dan is much richer and more jazz-influenced than most other groups, so the sound of a mu major in this context will be different from the use of an "ordinary add2 chord" in the context of more simple chords.

In short:
Think of the Steely Dan mu major chord as a rather special way of voicing and using an add2 chord.

Playing mu-major chords on the piano and guitar

The idea of the mu major chord was almost certainly conceived at the piano. Although you can play the chord on the guitar as well as a keyboard, things are easier on the keyboard as there is much more freedom to choose different voicings.

The simplest keyboard voicing is obtained by starting with a simple major chord: left hand plays the root (1st), and the right hand plays a root position triad (1st, 3rd, 5th). In G major you would have the left hand playing G, and the right playing GBD.

For a mu major, all you do is swap the G (1st) in the right hand for an A (2nd). In other words, move your thumb up a note so the right hand now plays ABD. Easy!  

Listen Sound Example: plain G major followed by G mu major
(wav file, 179 KB)


One of the key features of the mu major chord is the dissonance that occurs between notes that are close together. It is this dissonance that, when balanced with the other more consonant notes, gives the chord something of an "edge" or a "bite". This dissonance usually occurs between the 2nd and 3rd of the chord (in the example above, the dissonance occurs between the notes A and B).

On a piano or keyboard, there is no problem in playing chords that contain notes that are close together - it is no more difficult to play a straight major chord than a mu major chord. On the guitar however, it can be more difficult to achieve this dissonance. Because there are only six strings to use, and you use just one hand to select the notes, the choices are more limited and mu major chord shapes may involve more of a stretch than simpler chords. Mu major chords that use one or more open strings are the easiest ones to play on the guitar, for example G mu: 3x020x, D mu: xx0252 and A mu: x0242x (see table of mu major guitar shapes below).

Some of the more common piano voicings of the mu major chord are more challenging to play on the guitar. For example, the G mu major chord described above (made of the triad A B D with a G in the bass) is no problem on the piano, but on the guitar is quite a challenge (chord shape: 3x743x). For guitarists, the answer is to try and find ways of using open strings in mu major chords wherever possible. Where this cannot be done, try alternative fingerings and positions for the chord. If you still run into problems with certain chords you will probably need to leave out the bass note and just play the top notes of the chord.

Guitar mu major chord shapes

Here are a few guitar chord shapes for the mu major that you can try. The shapes that use the open strings are the easiest, but to get a mu in any key you'll need to use the moveable shapes. These are relatively easy to play and can be moved up and down the neck to get mu majors in any key.

Note: the mu major chord needs at least four notes (1st, 2nd, maj 3rd, 5th). You can choose to drop a note or two from the shapes that use five or six strings.

Guitar chord shapes for the mu major chord
Open string shapes Moveable (bar chord) shapes
G mu: 3x020x A mu: 5x242x
D mu: xx0252 D mu: x5x252
A mu: x02420 A mu: 579655
C mu: x32030  
E mu: 024100  

Next: Mu major Part 2

Last updated: February 2017