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About the II Forty
The Quad II-Forty is a direct descendant of the legendary Quad II amplifier designed by Peter Walker, founder of Quad. It modernizes the original 1950s design by increasing power output from 15W to 40W RMS while retaining the uniquely simple and timeless circuit topology. The amplifier uses larger KT88 output valves in push-pull configuration, military-grade 6SH7 input valves, and a robust power supply with a 5U4G rectifier valve. The chassis has been enlarged to accommodate substantially larger hand-wired audiophile components including new mains and output transformers. The amplifier delivers fast, crisp, and detailed sound while producing sufficient output current for modern loudspeakers, including Quad's own ESL models. It is sold as a matched pair of monoblocs and was manufactured from 2004-2008 in small batches, making it a highly sought-after amplifier among discerning analogue music listeners.
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