Accuphase A-48S Class A Stereo Power Amplifier

Accuphase A-48S Class A Stereo Power Amplifier with 50 Watts into 8 Ohms

The A-48S incorporates state-of-the-art technologies to create a Class A power amplifier that delivers superb performance. Benefitting from years of ideal designs of high-performance units, the A-48S utilizes 6-parallel pull-push power MOS-FETs and boasts an output of 50 W into 8 Ohms, 100 W into 4 Ohms, 200 W into 2 Ohms, and 400 W into 1 Ohm at the same size as conventional models. The noise level has also been further reduced by 6%, while providing a damping factor of 1,000. The A-48S will bring the best out of any speaker, enabling you to enjoy unparalleled sound quality and expansiveness.

Ample Output Power

The Class A Driven 6-Parallel Push-Pull Power MOS-FETs in the output stage produce a linear output power of 50 W into 8 Ohms, 100 W into 4 Ohms, 200 W into 2 Ohms, and 400 W into 1 Ohm.

Excellent Noise Suppression Performance

Ideal gain distribution and other sophisticated techniques improve noise level suppression by 6% over conventional models.

High Damping Factor

With a damping factor of 1,000, the speakers can be driven with full control over the counter-electromotive forces to get the most out of your speakers.

Ideal Gain Distribution

Allocating a high gain (12.6×) in the signal input section with its superb noise suppression rating drastically reduces output noise.

Balanced Remote Sensing

Balanced remote sensing improves the damping factor by feeding back the GND at the same time as the signal output from the speaker terminals.

Instrumentation Amplifier

With balanced circuits in the signal input section, the amplification stage is comprised entirely of an instrumentation amplifier principle that equalizes input impedance on the + and – sides for excellent external noise suppression while providing optimal circuitry for a high-end audio amplifier.

MCS+ Circuit

By placing the voltage amplification stage in a two-parallel circuit layout, the MCS+ (Multiple Circuit Summing-up) circuit theoretically lowers the noise floor by about 30%.

Current Feedback Amplification Topology

The current feedback amplification circuit offers exceptional performance in the high range with almost no impact on the frequency characteristics even when gain is switched, resulting in natural and dynamic driving of the speakers.

Our Review

The Accuphase A-48S is one of those Class A power amplifiers that feels effortlessly capable the moment you settle in for a listen, blending a touch of engineering wizardry with a wonderfully expansive musical experience. Its 6-parallel push-pull MOS-FETs deliver impressively linear power - 50 watts into 8 Ohms right up to a hefty 400 watts into 1 Ohm - so it drives just about any speaker with calm, unflappable control. A raft of clever Accuphase technologies sit quietly under the bonnet, from an instrumentation amplifier layout and current-feedback topology to balanced remote sensing and the noise-lowering MCS+ circuit, all working together to reduce noise, sharpen responsiveness, and boost that remarkable damping factor of 1,000. The result is an amp that feels both refined and muscular, serving up clean, natural, and beautifully spacious sound that makes each listening session feel just a little bit special.