Electronic music production was originally accomplished using a variety of electronic components and conventional analogue recording techniques. Both the electronic components and the recording equipment are now being replaced by computer software. In this paper we present a comparative study of two popular new systems, Reason and Live, concentrating on the role of user-interface metaphors. We compare the two systems, identify the key ways metaphor is used, and describe how it affects usability of the systems focusing on the role that user-interface metaphor play in their design.