There are usually 13 of these musicians, who are sometimes called “Wiyaga”, to accompany a Wayang Purwa performance. They play at least 15 different kinds of instruments, and so a few of them play to instruments in different parts of the performance. At times, some or all of them sing, or clap in very sophisticated rhythms, perhaps while the pesinden are singing.

The most important musician is the drummer, who passes on to the rest of the orchestra the coded signal given by the dalang as to what or how to play. In other words, the other musicians follow the lead given by the drummer.

Like the knockers and rattles manipulated by the dalang, the sound of the drum also accentuates dramatic passages in the play.

The musicians sit cross legged on the floor before their instruments and behind the dalang.