Accuphase C-3900S Precision Stereo Pre-Amplifier

Name: Accuphase C-3900S Precision Stereo Pre-Amplifier
Brand: Accuphase
Availability: InStock

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The Accuphase C-3900S represents the highest expression of Accuphase’s preamplifier engineering—an exquisite fusion of cutting-edge circuit design, meticulous craftsmanship, and absolute musical purity. Building on the celebrated C-3900, the new C-3900S elevates performance even further, introducing enhanced ultra-low-noise technologies, refined mechanical engineering, and newly developed usability features that make premium audio more immersive than ever.

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Specifications

Frequency Response: BALANCED/LINE INPUT, 3 - 200,000Hz +0 -3.0 dB, 20 - 20,000Hz +0 -0.2 dB

Total Harmonic Distortion (for all inputs): 0.005%

Input Sensitivity: BALANCED 252mV, 0.5V Output 63mV. LINE 252mV, 05.V Output 63mV

Input Impedance: BALANCED 40 kilohms. LINE 20 kilohms

Rated Output Voltage, Output Impedance: BALANCED/LINE OUTPUT 2 V 50 ohms, RECORDER REC (with AD input) 252 mV 200 ohms

S/N Ratio, Input-converted Noise (gain selector: 18 dB): BALANCED 118 dB, S/N ratio (EIA) 113 dB. LINE 113 dB, S/N ratio (EIA) 118 dB

Maximum Output Level (0.005% THD, 20 - 20,000 Hz): BALANCED/LINE OUTPUT: 7.0 V, RECORDER REC (with AD input): 6.0 V LINE

Maximum Input Level: BALANCED/LINE INPUT: 6.0 V

Minimum Load Impedance: BALANCED/LINE OUTPUT: 600 ohms, RECORDER REC: 10 kilohms

Gain: (gain selector: 18 dB)＊Gain switchable to 12/18/24 dB: BALANCED INPUT → BALANCED OUTPUT: 18 dB, BALANCED INPUT → LINE OUTPUT: 18 dB, LINE INPUT → BALANCED OUTPUT: 18 dB, LINE INPUT → LINE OUTPUT: 18 dB

Loudness Compensation: 1: +2 dB (100 Hz), 2: +4 dB (100 Hz), 3: +6.5 dB (100 Hz)

Attenuator: -20 dB

Headphone Jack: Suitable impedance: 8 ohms or higher, Output level: 2 V (40 ohms)

Power Requirements: 230 V AC, 50 Hz (Voltage as indicated on rear panel)

Power Consumption: 60 Watts

Maximum Dimensions: Width 477 mm, Height 156 mm, Depth 412 mm

Mass: 25.3 kg, 33.0 kg in shipping carton

A premium preamplifier for breathing life into deeply emotional performances and songs.

Accuphase

Flagship Engineering, Refined to Perfection

At the heart of the C-3900S lies Accuphase’s most advanced implementation of its renowned AAVA technology: Dual Balanced AAVA. By running two fully balanced AAVA modules in parallel, the C-3900S achieves extraordinary linearity, vanishingly low distortion, and a level of quietness never before reached in an Accuphase preamplifier.

Noise performance is simply unparalleled—15% lower than the already world-leading C-3900, setting a new benchmark in Accuphase’s 53-year history.

A Chassis Built for Pure Sound

Inside the beautifully crafted aluminum enclosure is an obsessively symmetrical, fully modular layout. A massive toroidal transformer, housed in its own aluminum block, anchors the power supply, supported by twelve custom Accuphase 10,000 μF capacitors. Every circuit module is mounted on gold-plated boards designed for maximum stability, heat dissipation, and serviceability. This is precision audio architecture, executed without compromise.

Mechanical Excellence You Can Feel

Audio enthusiasts will appreciate the new custom-engineered volume sensor—an 8mm, CNC-machined shaft that glides with exceptional smoothness. Although the audio signal never passes through the mechanism, its tactile precision reflects the C-3900S ethos: every detail matters.

Advanced Noise-Cancelling Technologies

The C-3900S integrates several proprietary innovations that push achievable noise levels to the extreme low end:

High-gain input stage for improved noise characteristics from the very first amplification stage.
ANCC (Accuphase Noise and Distortion Canceling Circuit) to detect and neutralize unwanted artifacts at the I-V conversion stage.
Eight-parallel summing amplifiers that dramatically reduce theoretical noise, delivering pristine output across both line and balanced connections.

The result? A breathtaking black background that allows music to emerge with purity, depth, and holographic realism.

The input selector is also bespoke, designed for flawless, noise-free switching and outstanding user feel.

A More Capable, More Expressive Headphone Experience

Accuphase has redesigned the headphone amplifier from the ground up. The new fully discrete, parallel push-pull stage offers selectable gain (Low, Mid, High) and support for headphones from 8Ω upward. A five-step bass compensator enriches low-level listening, while the improved 115-step left/right balance control enables precise personal tuning.

Timeless Design, Future-Ready Performance

Maintaining the same elegant dimensions as the C-3900—but now slightly heavier due to its more robust internal structure—the C-3900S is a true reference preamplifier for those seeking the ultimate listening experience. It is a masterwork of analog engineering, built to reveal the full emotional and sonic beauty of every recording.

Accuphase

Who is this for?

The Accuphase C-3900S is designed for the most discerning audiophiles building a no-compromise reference system around separate components. It suits listeners who view the preamplifier as the absolute heart of their system—where ultimate transparency, control, and musical truth are non-negotiable.

This is a product for those already operating at the very top tier of HiFi, typically paired with ultra-high-end power amplifiers and revealing loudspeakers in carefully treated, dedicated listening rooms. The C-3900S excels in systems where every component is capable of extreme resolution, and where its ultra-low noise floor and Dual Balanced AAVA architecture can reveal the finest micro-detail and spatial information in recordings.

It is particularly well suited to long, focused listening sessions where system synergy and emotional engagement matter more than convenience or feature sets. Whether reproducing intimate acoustic recordings or large-scale orchestral works, it delivers a presentation that is effortless, expansive, and exceptionally controlled.

For listeners seeking what is effectively a “final destination” preamplifier—one that defines the reference point for signal purity and musical realism—the C-3900S represents Accuphase at its absolute peak.

May 1, 2026

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