Mu major chord

A mu major chord (signified by μ) is a somewhat unconventional name for an "add 2" or "add 9" chord. It is formed by adding a 2nd to a major triad; in other words, it is a chord constructed from the 1st, 2nd, 3rd and 5th degrees of the major scale. The mu major chord differs from a sus2 chord as a sus2 chord does not contain a 3rd.

Often, the mu major chord is voiced with the root (1) in the bass, and 2nd, 3rd, 5th and 1st in the upper register. Part of its "sound" is the presence of two "stacked" fourths in the upper register, between 2-5 and 5-1 (although this is softened by the presence of the major third). This stacked fourth's feature, also called "quartal" harmony, is more obvious when the mu major is voiced with the 3rd in the bass, and the 2nd, 5th and 1st above. The chord can also be voiced with the 9th (2nd) in the bass, although such voicings are generally known as "slash chords".

Origin of the name, and separately, the chord itself

The reference to this chord as "mu major" has been popularized by fans of the jazz-influenced rock group Steely Dan, as well as by the band members themselves. This chord is used extensively in their work, often arpeggiated at the end of musical phrases. The "mu major sound" is a distinctive idiom of Steely Dan's style. In a 1989 interview with Paul Zollo [http://www.granatino.com/sdresource/14zollo.htm] , Walter Becker explained that the use of the chord developed from trying to enrich the sound of a major chord without making it into a "jazz chord". They used it so often that it became a signature sound for the band. The reason they called it "mu major" is now forgotten, but the whole business of naming the chord was meant as a joke about the band's perceived self-importance. While the name itself comes indeed from this band, whose quality is today undisputed and widely recognized by the industry, the usage of the chord itself has been present for decades in jazz music from bop to free, and was especially present in the Jazz-funk era from the late '60s to the early '80s. Notable users are, amongst many others and for instance, vibes player / composer Roy Ayers, or pianist / composer Herbie Hancock. The chord / voicing technique was the same but just not named as such.

External links

* [http://www.jmdl.com/howard/steelydan/mu-major.html Detailed explanation of the Mu major chord, including sound files extracted from Steely Dan recordings]