Leak TL/12 'Point One' amplifier, c 1952-1955.
© Science Museum / Science & Society Picture Library
H J Leak & Co, established 1934 by Harold Joseph Leak (1907-1989), first released the TL/12 audio power amplifier in 1948, heralding an advance towards domestic high-fidelity sound reproduction. With an output of 12 Watts at 0.1% distortion, and a stable, sensitive 3-stage circuit, the TL/12 was the most popular British amplifier of its day. Modified versions of the TL/12 were produced until around 1955, with the original bronze-coloured stove enamel finish being replaced with a gold finish in about 1952.