Amplifier designer John Cooper dies aged 71

John Cooper, a former Selmer Amplifier and designer of the Proamp and KMD ranges of amplifiers, has died at the age of 71.

Cooper began his amplifier career working for Henri Selmer and Co in Braintree, Essex, first hired as a test engineer and fault finder on production amplifiers. He was then promoted to design, working on circuit development and layout and design for Selmer. Cooper left Selmer in 1972, and began working for Miller Organs, designing and repairing electronic church organs.

In 1980, he went on to co-found amplifier brand Proamp, alongside Roger Haines. Proamp’s first products featured solid state preamps and valve power amps but other models including all-valve designs followed. In the US, the amplifiers, which were distributed by Kaman, were badged KMD. Difficulties with Kaman led to the eventual closure of Proamp as a manufacturing company, though the name lived on in the form of John’s Halstead repair business, registered as Proamp. The company maintained a large stock of both Proamp and KMD parts and spares.

According to MI Trade news, Cooper was poised to launch a new range of all-valve heads and combos, provisionally known as Hot Bottle. The future of this project is reportedly still to be decided.