Structured Audio Orchestra Language (SAOL) is an imperative, MUSIC-N programming language designed for describing virtual instruments, processing digital audio, and applying sound effects. It was published as subpart 5 of MPEG-4 Part 3 (ISO/IEC 14496-3:1999) in 1999. As part of the MPEG-4 international standard, SAOL is one of the key components of the MPEG-4 Structured Audio toolset, along with: * Structured Audio Score Language (SASL) * Structured Audio Sample Bank Format (SASBF) * The MPEG-4 SA scheduler * MIDI support