A natural approach to increasing the performance of musical applications is to exploit their inherent parallel structure on general-purpose multi-core architectures. In this paper, we discuss opportunities for exploiting parallelism in audio DSP graphs as well as within select audio processing components. We describe Tessellation OS, an experimental operating system structured around resource distribution, performance isolation, and QoS guarantees, and Lithe, a user-level runtime framework that enables construction of composable, application-specific schedulers. We present the design and implementation of a realtime parallel musical application on top of Tessellation OS and conclude with some preliminary experimental results.