Practical Devices Corporation (abbreviated PDC) is a privately-owned company which designs, manufactures, and sells high-end headphone amplifiers. PDC's portable products are notable for having a very rich set of features, despite a small physical size; for example, PDC is unique among audio manufacturers in that it is the only company to offer active variable crossfeed in a portable amp. Also noteworthy is the company's unconventional demonstrations of the mechanical strength of its products; an amplifier has, on occasion, survived being run over by a BMW. The company was incorporated in 2001, and is based in Toronto, Canada, with all manufacturing being done on-site in Toronto.