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Commercial Quad II Forty Mono Amplifiers This is a PAIR of these great little valve monoblocks. Excellent condition trade-ins. Condition: Excellent Payment Method: Paypal, EFT, Cash on Pickup Region/State: (VIC) Victoria/Australia By Class A Audio 0 Comments Secure Ad AUD $4,900 Date: January 30Jan 30
At A$4,900, this sits above the A$3,700 example seen for a used unit and well below the current A$8,000 RRP, so it reads as a fair-to-strong ask rather than a bargain-basement find. For a clean, working piece, the price looks sensible for a serious valve power amp with cult status, but it is not cheap enough to call a steal unless there are extras or exceptional provenance.
The appeal is the classic Quad sound: refined, dimensional, and easy to live with, with enough power for a wide range of real-world speakers when paired sensibly. In excellent condition, the upside is mainly in reduced risk and better resale, and that matters with older tube gear; I’d still want to confirm service history, output tube age, and whether it’s been properly checked before being run hard.
Independent perspective — not a price guarantee. Always verify condition, accessories and provenance before purchase.
Quad, the venerable British hi-fi brand, traces its origins to 1936 in London, when engineer Peter J. Walker founded S.P. Fidelity Sound Systems, soon renamed the Acoustical Manufacturing Company. Relocating to Huntingdon in 1941 after wartime bombing, the firm shifted from public address gear to domestic audio amid post-war demand for superior sound reproduction. Walker's pioneering ethos—prioritizing "the closest approach to the original sound"—defined Quad from its early QA12 amplifiers, adopted by the BBC, to the iconic Quad I of 1953.
The brand excels in amplifiers and electrostatic loudspeakers, revolutionizing both categories. The Quad II power amplifier of 1953 introduced cathode coupling for vanishingly low distortion, while the 1956 ESL 57 delivered the world's first full-range electrostatic speaker, employing a massless film diaphragm for unparalleled transparency and transient speed. Quad advanced into solid-state with the 1967 303 and transistor designs featuring innovative "Triples" output stages, later expanding to integrated amps like the 99 series, moving-coil speakers, and modern electrostatic models such as the ESL 988 and 989.
Today, under the International Audio Group since 1997, Quad holds a prestigious position in the high-end market, revered by audiophiles for its unyielding pursuit of accuracy over trends. Its heritage components command vintage collector status, yet contemporary offerings maintain a niche boutique appeal among discerning buyers seeking refined, distortion-free reproduction that honors Walker's legacy.
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