Accuphase E-303 (1983)

Name: Accuphase E-303
Brand: Accuphase

High-end integrated stereo amplifier with MOSFET output and direct-coupled phono stages, released in December 1983.

Overview

The Accuphase E-303 is a high-end integrated stereo pre-main amplifier released in December 1983. It was designed with consideration for digital sources like PCM and CD, leveraging technology from Accuphase’s high-grade separate components. The amplifier features a balanced, symmetrical circuit configuration in the preamp section and delivers 150W/ch into 8Ω with exceptionally low distortion. It includes a fully discrete, FET-based phono stage for both MM and MC cartridges, with switchable MC input impedance (10Ω, 30Ω, 100Ω) and a dedicated flat amplifier before the EQ stage for minimal signal loss.

Specifications

Power Output (8 Ω)	150W/ch
Total Harmonic Distortion	0.01% (20Hz–20kHz, >4Ω)
Frequency Response	20Hz–20kHz ±0.2dB (main amp, rated output)
Damping Factor	150 (8Ω, 50Hz)
Input Sensitivity / Impedance (MM)	2.7mV / 47kΩ
Input Sensitivity / Impedance (MC)	0.085mV / 10, 30, 100Ω selectable
Preamp Output	1.4V / 200Ω
Tape Rec Output	170mV / 200Ω
Headphone Output	0.4V, 4–100Ω
Tone Controls	10-step, ±7.5dB in 1.5dB steps (Bass: 200Hz/500Hz, Treble: 2kHz/7kHz)
Subsonic Filter	17Hz, -12dB/octave
Power Supply	100/117/220/240VAC, 50/60Hz
Power Consumption	550W (8Ω rated output)
Dimensions	445 × 160 × 370 mm (W×H×D)
Weight	20.5 kg
Original Price	¥298,000 (Japan, 1983)

Design

The E-303 uses a triple push-pull output stage with six MOS FETs, providing a 600W P_D margin. The entire signal path—from MC head amp to power output—is directly coupled, eliminating capacitors in the signal chain and using DC servo circuits to prevent drift. The phono preamp is FET-based with dual FET packages and thermally bonded transistor pairs. The MC input uses a dedicated flat amplifier before the EQ stage, and the tone control is a precision switch-type with 1.5dB steps. Signal routing uses gold-plated, hermetically sealed crossbar relays placed close to inputs for minimal path length. Illuminated VU meters display logarithmic peak levels referenced to 8Ω.

Context

The E-303 is part of a lineage that began with the E-202, Accuphase’s first integrated amplifier (1973). It evolved from the E-305 and shares design philosophy with other models like the E-302 and E-305V. The E-303X variant features solid aluminum rotary potentiometers instead of the base model’s linear slide pots, which some reviewers prefer for durability and value. Accuphase, founded in late 1972 by former Kenwood engineer Jiro Kasuga, built its reputation on high-grade separates before refining those designs into integrated units like the E-303.

Market

Current market prices range from €1,800 to €3,499, depending on condition and region. Common issues include dry solder joints, failed mute relays, DC offset drift, and degraded capacitors requiring recapping. Some units are advertised as overhauled ("revidiert") or fully recapped. Maintenance often involves replacing thermal pads, repairing traces, and servicing connectors damaged by mishandling.