Rogers Cadet II (1962–1964)

A dual-chassis valve amplifier system from the early 1960s, with a modular design and a solid build.

Overview

The Rogers Cadet II is a dual-chassis valve amplifier system made by Rogers in London between 1962 and 1964. It comes as three separate units: a main amplifier, a control unit, and an optional phono pre-amp. It was designed for high-fidelity audio and uses ECC83 and ECL86 valves with a selenium rectifier. The front panel has a tape socket, a mono button for radio, and two filters. It was used with speakers like the Denton, and it has a warm, hummy sound that punches above its weight.

Specifications

Output (claimed)	12W output
Output (measured example)	6.5 watts into 15 ohms
THD	At 4 watts, THD was around 0.2%
Tubes/Valves	ECC83/ECL86 tubes
Rectifier type	selenium rectifier
Speaker impedance options	several impedence terminals for different speakers
Output transformer core material	Not ferrite cored

Design

The Cadet II is built on two chassis. The internal wiring is neat point-to-point, with no PCB or tag board - components are strung between pillars on the chassis. The phono stage is controlled by an octal plug-in device, which lets you select between ceramic and magnetic types. The front panel carries a light, two filters, and a tape socket. The modular layout of main amp, control unit, and optional phono pre-amp makes repair and servicing easier. Original units used carbon composition resistors and Mullard valves.

Context

Rogers International was founded in London in 1947 by Jim Rogers. It began with public address equipment and moved into hi-fi speakers in the 1950s. The Cadet II was part of the company's early foray into amplification, before its later fame with the BBC LS3/5A monitor. It is considered rare and desirable today, but it was somewhat overlooked in its time. It was succeeded by models like the Cadet III and Cadet V, which drew on its design.

Market

Collectors want the Rogers Cadet II more and more. Used units have sold for €700 (2023) and £100 (1998). Common problems are disintegrated white plastic push buttons, discolored control unit fronts, drifted or open carbon composition resistors, hum, crackling valve holders, faulty volume controls, and damaged front-mounted DIN tape sockets. The front panel light may need a tap to work. ECL86 valves are no longer in production, so only NOS and used units are available, at high prices. Typical restoration is capacitor replacement and resistor checks. The circuit diagram (6975-03) is sought after for repairs.