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QUAD Classic II Monoblock Valve Amplifier paar/pair

Article code: BU25

QUAD Classic II Monoblock Valve Amplifier  paar/pair

QUAD Classic II Valve Amplifiers - 2x Mono

Arguably one of the most important products in the history of hi-fi was the Quad II power amplifier. Now, nearly fifty years after the original, we have launched the Quad II-forty valve amplification system and the Quad II classic power amplifier. For many audiophiles, the age of the transistor left a big hole in the emotion and pleasure provided by good valve amplification. The hi-fi world became orientated around numbers and statistics and choosing a new product was simply a question of numerical specifications.
Based on the styling of and reflecting Peter Walker’s circuit topology from the original, but brought up to date by the remarkable skills of our mechanical and electrical engineers, these new systems bring a richness and weight to any recording without the colouration many expect from such amplifiers. Not only are these some of the finest sounding valve pre/power combinations available today, but the genuine heritage and craftsmanship of the original has been preserved in the styling which can only be described as exquisite.

A faithful reproduction of the original, the new Quad II-classic offers audiophiles the chance to recreate the spirit and atmosphere produced from one of the most famous amplifiers in audio history. The original Quad II was first launched in 1953, designed by Peter Walker. At the time, many of his contemporaries were also producing good quality valve amplifiers. The Quad II looked, in comparison, very simple and unassuming, but its performance was far beyond that which its diminutive dimensions might suggest. The property which set the Quad II amplifier apart from other amplifiers of the time was its output stage. It was arranged such that the cathode coupled circuit emulated the performance of triode operation, but with the size and efficiency characteristics of pentode operation. It was this breakthrough that ensured the Quad II was to remain in continuous production until 1970. Peter’s circuit, notably the design of the output transformer, has become the stuff of legend amongst electronics engineers. Studied and analysed by the finest minds in the industry, the elegance and coherence of the design is still regarded as a reference today.

Given the quite modest components of the day, he was able to engineer something which was quite literally greater than the sum of its parts. The Quad II-Classic has been recreated accurately with output valves and input valves the equivalent of those used in the original design. The same balancing act has been employed to ensure the same wealth of detail and gentle tone of the original. The output valves produce around 15watts per channel, operating in Class A which, although slight by modern standards, allows a gloriously sweet and refined sound with appropriately matched contemporary loudspeakers.

Description Quad Classic II Tube monoblock power amplifier:
Tube complement: two EF86, two KT66, one GZ34.
Output power: 15W (11.8dBW into 8 ohms).
Frequency response: 10Hz–20kHz, ±0.2dB.
Input sensitivity: 570mV for rated power.
Rated load impedance: 8 ohms.
Damping factor: 11.75 at 700Hz, equivalent to a source impedance of 0.68 ohms into 8 ohms.
THD: 0.08% at 12W/700Hz.
Residual hum and noise: better than –90dB.
Dimensions in mm: 315 D by 165 H by 120 W.
Weight: 8.3kg.