Accuphase A-48S Stereo Power Amplifier

Features

The A-48S features an advanced mono-block construction with independent power amplifier engines for the left and right channels, supported by a custom-made high-efficiency toroidal transformer and large 68,000μF filtering capacitors. Its amplification stage incorporates a six-parallel push-pull MOS-FET configuration, reducing output impedance and ensuring reliable performance under various conditions. The balanced signal input section employs instrumentation amplifier principles to minimize external noise, further enhancing audio purity.

Designed for both performance and user convenience, the A-48S includes high-sensitivity analog meters, a front-panel gain selector with four levels, and dual speaker terminals for added flexibility. Safety and reliability are bolstered with advanced protection circuits using photo-couplers and temperature sensors, safeguarding the amplifier during operation. This meticulous attention to detail ensures the A-48S delivers the nuanced Class-A sound quality Accuphase is renowned for, capturing every subtle musical expression with precision and emotion.

Specifications

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