In part one, we discussed the essence of the Steely Dan Mu Major chord, a major triad in root position with the second added and voiced alongside the third, and possible 3-note voicings on the guitar. In the second part, we look at the evolution of the Mu Major concept in the music of Walter Becker and Donald Fagan, and how to apply these ideas to the guitar.
The Steely Dan Mu Major chord evolved on subsequent albums as the music, and the West Coast Studio musicians performing it, leaned more towards a jazzy interpretation of chord changes, where dissonant intervals [major and minor 2nds], slant chords and quartal harmonies abound. Starting with Dr. Wu [from the Katy Lied album], the Mu Major concept was expanded to also include the minor chords feature. This approach relies on the bassist to indicate tonality. [root]since the chord voice replaces the root and/or fifth with other scale tones [tensions] to add dissonance and richness.
Aja’s Home At Last is a good example of this. Although played on the piano on the recording, these 3-note voices can be played on the guitar. The introduction is a G minor root position that is expressed on the 4th, 3rd and 2nd strings, with the second degree [A] replacing the G on string 4 [can we call this G Mu Minor?]. The second chord, the same strings, is an F mu major, that is, a triad in root position with G replacing F. The other 2 intro chords are A minor. [same as G Mu Minor, 2 frets higher] and Bb Mu Major [same strings, C D F].
After the introduction in G minor, the verse section [“I know this super highway, this bright familiar sun”] starts with an Ebmaj9 chord. This voicing is best described as a bar chord, Bb/Eb, that is, a Bb major triad with an Eb in the bass. This 4 note voice can be played on strings 5, 4, 3 and 2 [Eb Bb D F]. The bassist is playing Eb. However, like the Mu major and minor chords, the function of these chords can change if the bassist changes the root. For example, with the bass playing a C root, this becomes Cmin11 Eb/b3, Bb/b7, D/9, F/11]. This voice is also used in Green Earrings, by Royal Scam. Starting at bar 3 with Bb/Eb, the voice moves in full steps [Ab/Db, Gb/Cb].
Green Earrings also has an example of quartal harmony, which occurs during the Am7 vamp that harmonizes the first 8 bars of the verse. These are 3 note voices stacked in quarters. These voices were explored in particular by John Coltrane [McCoy Tyner’s work on Love Supreme, My Favorite Things, Transitions]Miles Davis [the quintet albums with Herbie Hancock], Bill Evans, etc in the 50’s and 60’s. The voice of the Am7, played on strings 3, 2 and 1, is DG C. With the bassist playing A, this voice sounds like Am11, but with G on the bass it’s a Gsus4 or G11, F on the bass is an F13, etc. Fourth chords are built up in fourths, unlike traditional triad-based harmonies. [built in 3rds]. When we reverse these stacked fourths, we end up with mu major and mu minor type voices. For example, the Am11 voicing of Green Earrings, when inverted, would be GCD, and inverted again, CDG, from low to high. This creates a second major dissonance between C and D. This interval is the essential characteristic of the mu major sound.