Spanning from the early Musical Telegraph and Electronic Sackbut, to the late EMS Synthi AKS and Moog Synthesizers, electronic music and musical controllers, particularly the keyboards, have enabled people from all walks of life and all around the world to produce and manipulate sound as a mean for creativity, expressions, and shared experience. Note that most of the expressive keyboard interfaces to date rest on a rigid and heavy structure. On the other hand, textiles are ubiquitous in our daily life. They are highly formable and palpable materials with a broad spectrum of patterns, structures, and textures, making them a great candidate for physical interfaces. Inspired by theremin's expressive controls and the soft and deformable tactile properties of knitted textiles, we have developed an interactive textile-based musical interface with a familiar layout of piano keys.