Integrated amplifiers — Arcam SA35

The SA35 belongs to the Arcam Radia series as a streaming integrated amp, engineered in Cambridge in the UK. Arcam announced it with the larger SA45 and the ST25 streamer as higher priced additions to the Radia range that had arrived a year earlier, with shipping targeted for autumn 2024 and a US price of USD 3,499 at announcement. UK pricing later settled at GBP 2,999. One case holds the power stage, line and phono preamplification, a DAC and a network player.

Key specs that matter

Arcam rates the output at 2 x 120 W into 8 ohm across 20 Hz to 20 kHz at 0.5% THD, and 200 W per channel into 4 ohm at 1 kHz. At 80% of rated power into 8 ohm, distortion is 0.002%. The line stage reaches 106 dB signal to noise (A-weighted, ref. 50 W, 1 V input), while the digital path reaches 110 dB with a 0 dBFS reference, and frequency response stays within 0.2 dB from 20 Hz to 20 kHz. The chassis is 432 x 344 x 99 mm (W x D x H), weighs 12 kg net and 14 kg boxed, and draws up to 700 W from the wall with standby below 0.5 W.

Engineering and use context

The amplifier section uses the fifth generation of Arcam's Class G design, which works in pure Class A at low output with no crossover distortion and brings in a secondary supply rail only when more power is demanded, so less energy turns into heat at idle. A linear toroidal transformer supply feeds the circuits, and the new digital board has six layers with a ground plane to keep noise away from audio parts. Conversion runs on ESS Hyperstream IV chips in a balanced configuration. Network playback over 802.11ax Wi-Fi on 2.4 and 5 GHz handles files up to 32 bit and 384 kHz and DSD256 with gapless support, and Arcam lists Roon Ready, AirPlay, Qobuz Connect, Google Cast, Tidal Connect, Spotify Connect, internet radio, podcasts and UPnP, with three years of Roon included. A bonded 6.5 inch screen displays album art and track data, and setup runs through the ARCAM Radia app.

Pairing

Three RCA line inputs and a phono stage for both MM and MC cartridges take analogue sources, and HDMI eARC, two coaxial and two optical inputs accept TVs and disc players at up to 24 bit and 192 kHz. Bluetooth 5.4 with Snapdragon Sound and Auracast adds wireless sources. Two subwoofer outputs let a pair of subs be added to a system.

Alternatives

The Arcam SA45 is the more powerful Radia streaming amplifier, rated at 180 W per channel into 8 ohm and fitted with an 8.8 inch display.