The predecessor of Brass Plus had its origin in New York City in 1967, when bass trombonist Jim Morris formed the Contemporary Brass Quintet. While the instrumentation of this group was strictly classical, its musical sensibilities were not. The group combined jazz, classical, and even avant-garde elements and conceived a new and exciting sound. It gained recognition via its performances at such prestigious venues as the Lincoln Center Recital Hall and through the 10 albums it recorded for Music Minus One.
Morris moved to Southern California in 1974, where he soon began re-forming his ensemble. This time it would take the form of a nonet based on the instrumentation of the Contemporary Brass Quintet, but with a rhythm section added. The group, called Brass Plus, was a logical extension of the Contemporary Brass Quintet. It offered all of the rich sonorities and timbral colors of the quintet, but placed them in a solid rhythmic context. While the stylistic sensibilities of the original group were retained, the range of sonic possibilities offered by the new format was greatly expanded; the band could play anything from a classical chorale to a lilting jazz waltz to a pounding rock beat.