Sugden Masterclass PA-4 Phono Amplifier

The Sugden Masterclass PA-4 Phono Amplifier delivers a high-fidelity listening experience for vinyl enthusiasts. It features two moving coil (MC) inputs and one moving magnet (MM) input, offering versatile compatibility with various cartridges. Is equipped with factory-set, infinite loading options to precisely match cartridge specifications, enhancing sound quality. The PA-4 uses a Class ‘A’ current feedback circuit for MC stages and a Class ‘A’ voltage feedback circuit for MM stages. RIAA correction is integrated into the negative feedback loop for accurate frequency response. Its DC servo circuits provide direct coupling from input to output, ensuring pure signal transmission. The current shunt power supply incorporates a custom voltage regulator to maintain consistent performance across frequencies. Key specifications include a 360mV output, input sensitivity of 3.5mV for MM and 0.15mV for MC, and a signal-to-noise ratio greater than 70dB. The amplifier’s design prioritizes transparency and natural sound, with gold-plated circuit boards hand-assembled for long-term stability.