‘It is Sweeney’s Third String Quartet, from 2004, that has the word masterpiece stamped all over it. It is a monster of a piece lasting 36 minutes. It’s totally abstract, and some might think it discontinuous, with its apparently fractured progression, pounding rhythmic unisons that dissolve, seemingly isolated and unrelated musical events, wild dances, and melancholic intensity. With a little familiarity, the events begin to cohere, and what emerges is a kaleidoscopic piece of a rare conciseness and almost Beethovenian intensity’. – Michael Tumelty, The Herald, 2007