Quad QII-Eighty Power Amplifier

Description

Designed by Tim DeParavicini, the Quad II-Eighty takes inspiration from the original Quad II amplifier. It is an 80-Watt mono power amplifier following in the tradition and philosophies of Peter Walker. The output section consists of 4 KT88 valves running as two pairs in push-pull with the hallmark Quad topology of partial cathode loading in the output transformer.

Specifications:

Input Sensitivity (nominal) -1V RMS for full output
Power Output – 80W RMS
Output Impedance – 4 Ohms or 8 Ohms, selectable
THD @ 80 Watts – 2 x EF86, 0.5% – 30Hz – 15kHz, 1.0% – 20 – 20kHz
Residual Hum and Noise – Better than -94dB
Frequency Response – 10Hz – 30kHz (+0dB, -0.5dB), 3Hz – 50kHz (-3dB)
Damping Factor – 16 @ 1kHz (referred to 8 Ohms)
Power Consumption – 240VA maximum
Valves 2 x 6SL7, 1 x 6SN7, 4 x KT88