The Quad II Forty power amplifier is designed for music lover. It is a direct descendant of the legendary Quad II amplifier designed by Peter Walker, founder of Quad and one of the guiding lights of early Hi-Fi reproduction. Like the Quad II Forty uses the uniquely simple and timeless circuit topology developed by Walker. The modern listener demands a higher power output than the 15W of the original Quad II. The new amplifier uses larger output valves and a more robust power supply and the input valves have been upgraded to military grade devices.