Accuphase P-350 (1994)

Name: Accuphase P-350
Brand: Accuphase

Stereo power amplifier released in July 1994 with high current output and precision current feedback design.

Overview

The Accuphase P-350 is a stereo power amplifier made by Accuphase Laboratory, Inc. and released in July 1994. It delivers 150 watts per channel into 8 ohms. The design aims at high fidelity and natural sound. Accuphase lists it among its "Classic Models Reference," noted for excellent performance, high purity, and natural music playback in a simple design, with improved sound quality through natural energy response.

Specifications

Power Output (stereo)	150W/ch into 8Ω, 180W/ch into 6Ω, 210W/ch into 4Ω
Power Output (monaural, bridged)	420W into 8Ω, 300W into 16Ω
Total Harmonic Distortion	0.02% (20Hz–20kHz, 4Ω–16Ω load)
Frequency Response	20Hz–20kHz ±0.2dB; 0.5Hz–160kHz –3dB at 1W
Damping Factor	360 (stereo), 180 (monaural bridged)
Input Sensitivity (8Ω)	1.38V (full output), 0.11V (1W output)
Input Impedance	20kΩ unbalanced, 40kΩ balanced
Gain	28.0 dB (stereo and monaural)
Power Consumption	65W (idle), 300W (rated per Electrical Appliance Law), 490W (at 8Ω full output)
Dimensions	475 mm (W) × 170 mm (H) × 435 mm (D)
Weight	23.6 kg
Power Supply	100 VAC, 50/60 Hz

Design

The P-350 uses a current feedback amplifier circuit. The balanced input connects directly to the non-inverting (+) and inverting (-) inputs of the input stage. The output stage has four parallel high-power multi-emitter transistors, rated at 100W collector loss and 10A collector current. The power transformer is 700 VA. Two 40,000 μF/71WV aluminum electrolytic capacitors give 2.8 coulombs total charge capacity. The printed circuit board uses gold-plated copper foil. Input terminals are gold-plated too. The speaker terminals are large machined brass and take banana plugs and bi-wiring. For monaural use, it can be bridged.