Quad QII-Forty Mono Power Amplifier (Pair) A Modern Tribute to a Classic Design The Quad QII-Forty Mono Power Amplifier reimagines the iconic Quad II amplifier, blending vintage aesthetics with contemporary engineering. Designed by Tim de Paravicini, this amplifier maintains the original's cathode-coupled circuit topology, ensuring a harmonious balance between warmth and clarity. Robust Valve Configuration Equipped with two KT88 output valves, two 6SH7 input valves, and a 5U4G rectifier valve, the QII-Forty delivers 40W RMS in pure Class A operation. This configuration provides ample power to drive modern loudspeakers, including Quad's own ESL series, with ease and precision. Enhanced Performance The QII-Forty boasts impressive specifications: Total Harmonic Distortion (THD): 0.3% at 40W and 0.03% at 1W at 700Hz Frequency Response: 10Hz to 30kHz ( 0dB, -0.5dB) Residual Hum and Noise: Better than -80dB Damping Factor: 20 at 700Hz (referred to 8 Ohms) These figures reflect the amplifier's ability to reproduce audio with exceptional clarity and minimal distortion. Versatile Loudspeaker Compatibility The QII-Forty offers selectable 4 and 8-ohm loudspeaker taps, providing flexibility to match a wide range of loudspeakers. This versatility ensures optimal performance across different speaker impedances. Specifications Feature Details Power Output 40W RMS Total Harmonic Distortion 0.3% at 40W, 0.03% at 1W at 700Hz Residual Hum and Noise Better than -80dB Frequency Response 10Hz to 30kHz ( 0dB, -0.5dB) Damping Factor 20 at 700Hz (referred to 8 Ohms) Power Consumption 180VA maximum Loudspeaker Taps 4 and 8 Ohms Input Valves 2 x 6SH7 Output Valves 2 x KT88 Rectifier Valve 1 x 5U4G Input Sensitivity 1V RMS Dimensions (H x W x D) 185 x 200 x 390 mm Weight 18.3 kg
