Spendor BC1 (late 1960s)

Bextrene was the material of choice for the speaker diaphragms in Spendor’s first pair of speakers, the BC1. A product of BBC engineer Spencer Hughes (co-founder with Dorothy Hughes, hence the Spendor name) and codesigner Dudley Harwood, the BC1 speakers hada three-way design: the 8-inch Bextrene mid/bass driver (the only commercially-available Bextrene driver), a Celestion HF 1300 tweeter (ranging between 3kHz and 13kHz) and a Coles (not that Coles) 4001 G supertweeter (above 13kHz). They were fed by a nine-element crossover, comprising film capacitors for frequency and temperature stability, and radio metal-cored chokes that allowed for high transients and low resonances.

The BC1s hit the market in the late ’60s and found their way into broadcast and recording studios before eventually being available to buy for consumers. Some 600 pairs were supposedly in operation at the BBC at one time — and one of those pairs now resides with your humble Editor.