Just this morning when attending the weekly school recital hour, I recalled that every bit of Weather on Welcome to Night Vale that I had analyzed was text-based. I wondered if an instrumental work would be coming up, I couldn't remember from my binge-listening last fall. And Night Vale delivers, with a piece by the daKAH Hip Hop Orchestra. A 2007 article on About.com describes this group as around 60 musicians, including rappers, DJs, and singers. The piece on Welcome to Night Vale, "Movement 1: Invocation of the Duke," sets up a latin beat with low saxophones, percussion, and some subtle record scratching. The repeating eight-bar bass line hovers around scale degree 5 of a harmonic minor scale, occasionally jumping around to grab some additional notes, but never resting on tonic. Over this beat, two violins trade eight-bar solos. The first entrance is rough, the rhythms don't quite fit the 4+4 phrase that the bass line has established, but after this rushed entrance the rest of the solos continue the latin beat on the harmonic minor scale. The augmented seconds give an exotic feel to the solos, along with the continued avoidance of tonic as a resting point. Right at the Golden Ratio of the chronological duration (63 out of 102 seconds), the violin solos stop and the brass starts playing a riff that slowly gets louder and more ornate, with high trumpet shakes and sustained string chords. By the end, I wasn't sure whether I should be hearing the E major chord as the dominant of A minor, or as its own tonic. That rotation of the A harmonic minor scale results in the E "arabic" scale, also called the Phrygian Natural 3 scale, or the Dominant b2 scale. One live performance by the Orchestra does pair this song with "Reap What You Sow," which is in the key of A minor, so that reinforces the feeling of "Invocation of the Duke" as an introduction.
Presumably the Duke that is being invoked is Duke Ellington. Another
track invokes The Clown, probably a reference to Charles Mingus. The podcast episode is "The Man in the Tan Jacket," who is a character that no one can clearly recall or describe. This haziness fits with the tonal ambiguity of "Invocation of the Duke," unclear whether it is an introduction or a stand-alone piece.