2021-04-122015-01-011817319519928645SCOPUS;2-s2.0-84949509559http://hdl.handle.net/10784/28598Writing music interaction systems is not easy because their concurrent processes usually access shared resources in a non-deterministic order, often leading to unpredictable behavior. Using Pure Data (Pure Data) and Max/MSP, it is possible to program concurrency; however, it is difficult to synchronize processes based on multiple criteria. Process calculi such as the Non-deterministic Timed Concurrent Constraint (ntcc) calculus, overcome that problem by representing, declaratively, the synchronization of multiple criteria as constraints. In this article, we propose the framework Ntccrt, as a new alternative to manage concurrency in Pure Data and Max/MSP. Ntccrt is a real-time capable interpreter for ntcc. Using Ntccrt binary plugins in Pure Data, we executed models for machine improvisation and signal processing. We also analyzed two case studies: one of a machine improvisation system and one of a signal processing system. We found out that performance of both case studies is compatible with soft real-time music interaction; it means, a musician can interact with Ntccrt without noticeable delays during the interaction. © 2005 - 2015 JATIT & LLS. All rights reserved.engAsian Research Publishing NetworkComputer musicConcurrent constraint programming (ccp)Machine improvisationMusic interactionProcess calculiSignal processingSoft real-timeinfo:eu-repo/semantics/article2021-04-12Toro, M.Rueda, C.Agón, C.Assayag, G.