Any Quad piece is always a welcome sight around the shop and the 405 power amplifier never fails to disappoint. It is a current dumping amplifier that has been around since the late 70s. In "current dumping," a low-powered, low-distortion class-A amplifier is used to control the amount of current passing through a pair of heavy-duty "dumping" transistors, and it is the latter which provide the driving power (100Wpc) for the speakers.
These amplifiers are known for their very natural sound and non-fatiguing presentation. In good condition with some top panel scratches.