• Power MOS-FETs in 6-parallel push-pull configuration
• Linear output characteristics over entire load impedance range
• Strong power supply with massive toroidal transformer and large 60,000 μF filtering capacitors
• Instrumentation amplifier principle
• High-gain signal input section in discrete configuration
• Dedicated power supply for signal input section
• Polarity switching for balanced input connectors
• MCS+ circuit topologys
• Current feedback principle in amplification circuitry
• Protection circuitry using MOS-FET switches
• High damping factor of 800
• Speaker output protection circuit guards against short-circuiting
• Two sets of large speaker terminals
• 4-step gain control
• Support for bi-amping and bridged mode
• Aluminum top plate with hairline finish

The A-48 employs an instrumentation amplifier configuration that is highly effective in keeping external noise from affecting the signal transmission lines. Furthermore, the input stage is designed for high gain (22 dB) and the power amplification stage for low gain (6 dB). Consequently, the signal emerging from the signal input section has a large amplitude which makes it much less prone to external interference, thereby further improving the noise performance.

Similar to the higher-ranked A-75, the signal input stage of the A-48 is entirely configured with low-noise discrete circuit components. This makes it possible to design the circuit for a high gain of 22 dB (a multiplication factor of approx. 12.5), something that cannot be achieved with OP amp ICs. As a result, the S/N ratio of the amplifier is an astonishing 117 dB.

Linear output characteristics over entire load impedance range