The hear of today’s Harbeth sound is our unique, Patented, RADIAL™ cone material. It has an interesting legacy. On 19 March 1976, our founder, H.D. Harwood of the BBC Research Department, filed a Patent application (1563511) claiming that polypropylene could be used a loudspeaker cone material, now the de factor cone material is throughout the global audio industry. The Harbeth company was formed to commercialise his invention and to sell his knowledge as monitor speakers back to the BBC. However, in 1994/5, a superior material was presented to Harwood and analysis of its improved properties led Harwood to abandon polypropylene and adopt the new TPX material in the forthcoming HL Monitor Mk4, and later in my (A.S) original Compact and HL5. In 1990, concerned by the scarcity of supply of bought-in cones, we won a British Government Science & Engineering Research Council (SERC) Research Grant. This project allowed us to thoroughly examine alternative material solutions concluding that there was no undiscovered ‘off the peg’ wonder material, and to inventing and Patenting our own plastic formulation, called RADIAL™ [from Research and Development In Advanced Loudspeakers]. RADIAL™ is still unbeatable for clarity and resolution.