The use of other instruments, such as brass or woodwind instruments, as accompanying instruments is usually limited to a few background riffs, or repeated phrases. This type of accompaniment is popular in blues bands. Usually one horn player will play a simple line based on the blues scale, and other horn players will pick it up and repeat it.

Free jazz forms allow for less structured accompaniment. If you listen to Ornette Coleman’s Free Jazz, or John Coltrane’s Ascension, you will notice that the horn players who are not soloing are free to play whatever background figures they want. The result is often cacophonous, but if that is the desired effect, then that is not bad in itself.

At the other end of the spectrum are big band arrangements, which often have intricate written out horn backgrounds for solos. Arranging for horn sections is similar to accompanying on piano in that the parts generally form voicings of chords and are used in a rhythmically interesting way. The parts are generally smoother and more melodic than a typical piano accompaniment, however, both because the piano part is usually improvised whereas the horn arrangement can be preplanned, and because it is easier for a horn section to play melodic lines voiced in chords than it is for a pianist. Horn section arrangements often emphasize articulation, or variations in attack and dynamics, more so than a piano is normally capable of. Commonly used devices in horn section arranging include the use of sforzando, or notes of sudden loudness; alternating staccato, or short note, and legato, or long note, passages; bent notes, or notes in which the player alters the pitch briefly while playing, and falloffs, or notes in which the player rapidly lowers the pitch, sometimes by an octave or more, usually to end a phrase.

You do not have to play in a big band or be an accomplished arranger to use horn section accompaniment. Often two or three horns are enough to play interesting background figures. Most of the same principles used in piano voicing can be used in horn section voicing. Drop voicings are especially effective. When there are only two horns, lines moving in parallel thirds often work well. Listen to Miles Davis’ The Birth Of The Cool, or any of Art Blakey’s recordings with the Jazz Messengers, for ideas on how one can arrange for relatively small ensembles. David Baker’s book Arranging And Composing can help get you started as well.