Accuphase C-290V Precision Stereo Preamplifier (1993)

Name: Accuphase C-290
Brand: Accuphase

A high-end stereo preamplifier with balanced transmission, discrete current feedback circuitry, and modular dual-mono construction, released in November 1993.

Overview

Accuphase Laboratory, Inc. released the C-290V Precision Stereo Preamplifier in November 1993. It is a stereo control amplifier built for maximum signal purity, using the balanced transmission technology developed from the C-280V. An optional phono equalizer unit, the AD-290V, installs through a rear-panel slot and handles MM and MC playback. The chassis is 8 mm thick hardened aluminum, and the cabinet is persimmon wood.

Specifications

Production Year	November 1993
Original Price	￥880,000
Frequency Response (Line Inputs)	3 Hz – 350 kHz (+0, -3.0 dB); 20 Hz – 20 kHz (+0, -0.2 dB)
Total Harmonic Distortion	0.005% at all input terminals
Signal-to-Noise Ratio (Balanced)	111 dB S/N; -123 dBV input conversion noise
Gain (Balanced/Unbalanced)	18 dB (line), up to 86 dB (MC with AD-290V)
Inputs	9 RCA pairs, 3 balanced inputs
Outputs	6 outputs
Power Consumption	30W
Dimensions	475 mm W × 149 mm H × 405 mm D
Weight	23.8 kg (24.8 kg with AD-290V)
Power Supply	100/117/220/240 VAC, 50/60 Hz

Design

The C-290V uses a current feedback amplifier circuit with balanced transmission technology. The line amplifier is a pure complementary push-pull discrete design. The signal path runs on Teflon-based glass fluorocarbon resin PCBs with gold-plated copper foil. There are four unit amplifiers, two per channel, and each sits in a thick aluminum enclosure with its own regulated power supply. The power section has dual amorphous-core transformers (Fe-based, 25 μm thickness) and separate filter capacitors, which keeps the left and right channels completely isolated. The volume control is a four-gang CP (conductive plastic) type with a rotating resistor design and a gold-plated multi-contact brush. Tracking error stays under 0.5 dB at -60 dB. Signal switching uses hermetically sealed, nitrogen-filled relays with gold and silver-palladium alloy twin crossbar contacts. A bridge feedback topology makes the balanced output stage possible. The phono module (AD-290V) can be added for MM/MC support, with selectable gain and impedance.

Context

The C-290V takes the balanced transmission technology first developed with the C-280V and refines it. It uses Accuphase’s proprietary current feedback design and a fully modular dual-mono layout. It sat as a flagship preamplifier in the brand’s 1990s high-end lineup.

Market

The C-290V originally sold for ￥880,000 in November 1993. Units in good condition with the optional AD-290V phono stage draw strong interest from audiophile collectors today.