Editing Swing era (section)

===Arranging===
To fit the new groove, dance-band arranging became more inventive. To some extent, this was a belated influence of Louis Armstrong, whose rhythms continued to be absorbed by soloists and arrangers through the 1930s. Arrangers learned to write elaborate lines for an entire section, harmonized in [[block chord]]s, called soli. They were conversant with chromatic (complex) harmony and knew how to make the most of their flexible orchestra.

Arrangements could also arise spontaneously out of oral practice. But even in New York, where bands prided themselves on their musical literacy, musicians could take improvised [[riff]]s and harmonize them on the spot. The result, known as a head arrangement, was a flexible, unwritten arrangement created by the entire band. One musician compared it to child's play—"a lot of kids playing in the mud, having a big time."

Both kinds of arrangements, written and unwritten, could be heard in the hundreds of recordings made in the 1930s by Fletcher Henderson. For flashy pieces, Henderson relied on experienced arrangers, from his brother Horace to Don Redman and Benny Carter. But his biggest hits emerged from the bandstand. One was "Sugar Foot Stomp", derived in the early 1920s from the King Oliver tune "[[Dippermouth Blues]]" and still in the repertory. By the 1930s, it had evolved into a thoroughly up-to-date dance tune, with a faster tempo to match the tastes of the dancers. Another hit was "[[King Porter Stomp]]",<ref>Giddins, Gary and Scott DeVeaux (2009). "The Swing Era." In ''Jazz'', 174-77. New York: W.W. Norton.</ref> a [[ragtime]] piece by Jelly Roll Morton that became radically simplified, shedding its two-beat clumsiness and march/ragtime form as it went. Many of these pieces were ultimately written down by Henderson, who became his band's chief arranger. His genius for rhythmic swing and melodic simplicity was so effective that his music became the standard for numerous swing arrangers. Henderson was fond of short, memorable riffs—simple, bluesy phrases—in [[call and response (music)|call and response]]: saxophones responding to trumpets, for example. In some passages, he distorted the melody into ingenious new rhythmic shapes, often in [[staccato]] (detached) bursts that opened up space for the rhythm section. Henderson was shrewd and efficient. He wrote only a few choice choruses, leaving the remainder of the arrangement open for solos accompanied by discreet, long-held chords or short riffs. As each piece headed toward its climax, the band erupted in an ecstatic wail.