Accuphase C-3900S Precision Stereo Preamplifier

For decades, Accuphase Laboratory Inc. has been regarded as one of the HiFi legends in precision amplification, consistently refining its circuit concepts rather than following short-lived trends. In high-end stereo systems, the preamplifier defines how transparently sources are connected, how precisely levels are controlled and how flexibly a system can adapt to different listening situations. This is exactly the environment in which Accuphase positions the C-3900S Precision Stereo Preamplifier as a thoroughly evolved reference solution.

Key Facts

• Reference precision stereo preamplifier with fully balanced, dual-mono architecture
• Dual Balanced AAVA volume control combined with integrated ANCC noise correction
• Eight parallel-operated output amplifier stages for high stability
• Extensive balanced and line-level connectivity for complex systems
• Comprehensive adjustment and memory functions for practical system integration

Dual Balanced AAVA and ANCC: control without sonic compromise

At the core of the Accuphase C-3900S lies the Dual Balanced AAVA volume control system. Unlike conventional designs that attenuate the signal using resistor networks, AAVA actively adjusts level by combining multiple amplifier stages with different gain factors. In the C-3900S, two fully balanced AAVA circuits are used per channel, further reducing noise and improving electrical stability.

This concept is complemented by ANCC technology, which actively compensates noise and distortion components within the signal path. Especially at low and medium listening levels, this approach is designed to maintain clarity and resolution, offering a practical benefit for realistic everyday listening rather than purely theoretical performance figures.

Fully balanced architecture and independent power supplies

The C-3900S follows a strict dual-mono design philosophy. Left and right channels are equipped with their own amplification stages, individual power supplies featuring dedicated toroidal transformers and separate filter capacitor banks. This consistent separation minimises crosstalk and ensures stable operating conditions regardless of signal level or connected sources. The carefully optimised circuit boards further support low-loss signal transmission, underlining the technical ambition of this preamplifier.

Connectivity as a key practical advantage

A central focus of the Accuphase C-3900S is the flexible integration of a wide variety of signal sources. On the input side, four balanced XLR inputs and six line-level inputs via Cinch connectors are available. In addition, dedicated EXT PRE inputs in both balanced and unbalanced form allow the integration of external preamplifiers or specialised signal processors.

On the output side, the C-3900S provides two balanced XLR outputs and two line-level Cinch outputs. Dedicated recorder connections for play and record are also included, which is particularly relevant for users of analogue tape machines or external recording devices. In practice, this makes the C-3900S suitable for both classic two-source systems and complex multi-component high-end installations.

Operating concept and headphone amplifier

Accuphase equips the C-3900S with a finely engineered operating concept centred around a precision mechanical volume sensor. This allows exceptionally smooth and low-noise level control, including motorised operation via remote control. Additional functions include selectable overall gain, finely adjustable balance control, a five-step loudness compensation and individually storable settings for each input.

The integrated headphone amplifier is built using discrete circuitry and offers selectable gain stages, enabling practical matching with headphones of varying impedance and sensitivity.

Price and availability

The Accuphase C-3900S Precision Stereo Preamplifier will be available through authorised specialist dealers. Information regarding pricing and exact market availability has not yet been announced.

Conclusion

With the C-3900S, Accuphase Laboratory Inc. presents a preamplifier that combines technical consistency, a fully balanced architecture and exceptional system flexibility. The further refined Dual Balanced AAVA volume control addresses fundamental limitations of conventional designs, while the extensive connectivity allows seamless integration into demanding stereo systems. As such, the C-3900S is clearly aimed at users who view the preamplifier as a long-term, stable control centre at the heart of their high-end audio system.

Technical Specifications