Sugden Audio

Sugden Audio is a British engineering company that manufactures hi-fi and audio equipment. Founded by James Edward Sugden in Cleckheaton, West Yorkshire in 1967,[1] the company is best known as the manufacturer of the Sugden A21 amplifier.

Sugden Audio
TypePrivate limited company
IndustryAudiovisual equipment manufacturing and distribution
HeadquartersHeckmondwike, West Yorkshire, United Kingdom
Key people
Jim Sugden
Richard Allan
ProductsHigh fidelity equipment
Audiovisual equipment

Sugden had been involved in the manufacture of scientific equipment since 1960 with his company Research Electronics.[1][2] Sugden was keenly interested in hi-fi, in particular in overcoming the problem of crossover distortion common in Class B solid state amplifier designs at the time. He developed a Class-A amplifier, the Si 402, which avoided this, however it was extremely expensive, costing 100 Guineas (£105, equivalent to £2,000 in 2021[3]) and few if any were sold.[2] At the time, Sugden was the only company in the industry using Class A design in their Hi-Fi amplifiers.[1]

The following year Sugden agreed to work with local loudspeaker manufacture Richard Allan, which would market Sudgen's amplifiers under their brand name.[4] In April 1968 the A21 amplifier was premiered at an audio fair in London. It would sell for a much more attractive £52 and received good reviews in the audio press.[4]

Shortly after they set up a factory at Carr Street in Cleckheaton in West Yorkshire and started producing the A21 amplifier under their own name.[1] They subsequently expanded their range of products to include other amplifiers and tuners.

In 1981 they relocated to Valley Road in Heckmondwike where they remain.


  1. ^ a b c d "Sugden Heritage". Retrieved 1 October 2017.
  2. ^ a b "The Si402". Retrieved 1 October 2017.
  3. ^ UK Retail Price Index inflation figures are based on data from Clark, Gregory (2017). "The Annual RPI and Average Earnings for Britain, 1209 to Present (New Series)". MeasuringWorth. Retrieved 11 June 2022.
  4. ^ a b "Richard Allan Class A amplifier". Retrieved 1 October 2017.