Arcam SA35: Class G network amplifier with Hi-Res streaming
October 28, 2025
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High-fidelity amplification is going through a period of profound transformation. Between purists devoted to analog circuits and fans of high-resolution streaming, Arcam offers with the SA35 a particularly accomplished technical synthesis. This 12 kg machine, developed in Cambridge, embodies a philosophy where traditional British engineering meets the demands of the contemporary digital era.
Arcam Class G: hybrid amplification technology explained
5th-generation Class G amplification: 20W Class A + 120W continuous power
The SA35 is built on a meticulously refined hybrid amplification approach. The first 20 watts operate in pure Class A, a topology renowned for linearity and the absence of crossover distortion. Beyond this threshold, the electronics switch to a more efficient mode, maintaining a total power of 120 watts into 8 ohms.
This dynamic architecture constantly monitors power demands and adapts the power supply accordingly. The analogy with a variable-displacement engine perfectly illustrates the principle: energy savings during subtle passages, with instant reserves available for orchestral crescendos. Total harmonic distortion remains contained at 0.002% at 80% of rated power.
Power supply and electromagnetic shielding
The linear power supply with a toroidal transformer adopts an unusual inverted mounting. This geometric arrangement keeps stray magnetic fields away from sensitive audio stages. The six-layer digital platform integrates a continuous ground plane, creating an effective electromagnetic barrier around critical components.
SA35 Hi-Res Streaming: ESS DAC and Roon Ready compatibility
ESS Hyperstream IV differential DAC: 32-bit/768 kHz PCM and DSD256
The digital-to-analog converter ESS Hyperstream IV operates in a differential configuration. This balanced topology, combined with advanced jitter elimination, preserves the temporal integrity of the digital signal. Compatibility extends up to 32-bit/768 kHz PCM files and DSD256.
Integrated streaming ecosystem
The streaming platform natively supports Apple AirPlay 2, Google Cast, Spotify Connect, Tidal Connect, and Qobuz Connect. Recently obtained Roon Ready certification unlocks advanced music management features. Bidirectional Bluetooth aptX HD enables both reception from mobile sources and transmission to wireless headphones.
SA35 connectivity: phono inputs, HDMI eARC, and 6.5-inch display
6.5-inch high-resolution display
The 6.5-inch front display shows album artwork and metadata in high definition. This visual interface, rare on an integrated amplifier, makes it easier to navigate large music libraries without systematically relying on the mobile app.
Analog and digital connectivity
The SA35 includes phono inputs for moving magnet and moving coil cartridges, preserving the vinyl heritage. The HDMI eARC input simplifies integration into an AV system, automatically retrieving the TV’s audio signal. Two optical and two coaxial inputs round out traditional digital sources.
SA35 Dirac Live: automatic room correction and setup
Operating principle
Dirac Live analyzes the listening room’s impulse response using precise test signals. Unlike conventional equalizers, this technology simultaneously corrects both amplitude and phase. The supplied microphone lets you take multiple measurements at different listening positions.
Impact on sound reproduction
Phase correction time-aligns the different frequency components. This synchronization improves bass coherence, midrange clarity, and stereo imaging precision. The two subwoofer outputs allow subwoofers to be integrated into the correction chain.
Press recognition
What Hi-Fi? awarded the SA35 five stars and an Award 2025, praising its sonic balance and versatility. Reviewers highlight the build quality and openness of the presentation, while noting room for improvement in the Radia control app.
Environmental approach
The SA35’s packaging eliminates plastics entirely, embracing a conscious eco-responsible approach. This attention to packaging materials reflects growing environmental awareness in the high-end audio industry.
The SA35 illustrates the technical maturity achieved by contemporary connected amplification. By combining proven technologies with digital innovation, Arcam delivers a versatile machine that adapts to modern use without denying its British sonic heritage. The integration of Dirac Live and Roon Ready certification makes it a compelling choice for music lovers seeking to optimize their setup without multiplying the boxes.