The Sugden A4II amplifiers smooth fatigue free listening owes much to the Class A circuitry of the power stages. The configuration has been chosen to give the maximum benefits of the better reproduction qualities of Class A and the economic output of Class B.
During the reproduction of both music and speech full output is required only during very short periods. Sugden had chosen a level of Class A operation which ensured the majority of your listening would be in Class A with short excursions into AB.
The amplifier was dynamic, with precise imaging, sound stage and separation normally found in more expensive “separates” combinations. The colour combination of light brown, orange and white was novel at the time and much talked about. Today the A48II would blend in as an art piece as well as a finely tuned music reproducer!