This article focuses on an expanded critical sound design practice drawing on the qualities of sound associated with embodiment, vocality, and memory. We argue for sound design as a critical tool in communicating design histories in museums, highlighting the case of a research-based pedagogical project between the Royal College of Art and the Victoria & Albert Museum, “The Sounding Object,” which united sound design, history, and critical museology. The project reveals links between sound design practice, history writing, and critical curatorship, demonstrating how sound enhances museums’ capacity to embrace the contingency of history, communicate in inclusive ways, and truly become “polyphonic.”