J.E. Sugden & Sons · A21 series

A21 Series 3

The 1972 revision of the A21, built through 1977 and the version most often found in collections today.

Catalogue code: A21 Series 3
Years: 1972–1977
Type: integrated amplifier (Class A)
Valves & speakers: 1972-1977; pure class A, single-ended voltage rail
Lifecycle: retired
Confidence: High

Specifications

Channels: 2
Technology: solid-state
Class_of_operation: A

Safety

Class-A unit: the chassis runs hot by design and needs free airflow. The supply capacitors are the usual failure point after 20+ years; Sugden still services the A21 line in the UK.

01 / Witnesses

What applies here

Marks that can be entered for this maker: Model / catalogue number, British capacitor code (Hunts, Mullard), Japanese capacitor code (Nichicon, Chemi-Con, ELNA), EIA component code, Version & era marker.

02 / Bounds

The model year is a floor

Nothing predates 1972; components only push the date later.

03 / Value

What moves the price

Sold-price aggregates are not collected yet, so the archive gives no figure — condition, originality of the transformers and a documented recap move this model more than any list price.