Arcam Integrated Amplifiers: A Complete Rundown of the Range

Arcam has been building amplifiers in Cambridge since 1976, and the company’s reputation has always rested on the same thing: a slightly warm, unfussy presentation that stays listenable for hours without dulling detail. The current range is the broadest it has been in years, spanning a £749 entry point to a £4,499 streaming flagship, and the models differ in ways that matter far more than the price ladder suggests.

Below we go through each integrated amplifier in the current line-up, what separates them technically, and who each one actually suits.

The Two Families

It helps to understand that the range splits into two distinct groups.

The Radia series covers the A5+, A15+ and A25+. These are traditional integrated amplifiers: analogue and digital inputs, a phono stage, Bluetooth, and no network streaming. You bring your own source. They share a design language of two aluminium dials, discreet illumination and an all-metal chassis.

The SA streaming amplifiers, the SA35 and SA45, add a full network streaming platform, a large display and Dirac Live room correction. They are complete systems that need only speakers.

Sitting slightly apart is the A50 Signature, a fiftieth-anniversary model that takes the traditional integrated format and pushes the amplifier architecture considerably further than anything else in the range.

A Word on Class G

Most of the range above the A15+ uses Arcam’s Class G topology, and it is worth explaining briefly because it shapes how these amplifiers behave. A conventional Class AB output stage runs from a single set of supply rails. Class G uses two: a lower-voltage rail handles the vast majority of the music, and a higher rail engages only when a transient demands it.

The practical effect is that the amplifier spends most of its time operating in its most linear region, running cooler and with lower distortion, while retaining significant reserves for peaks. It is why the Class G models feel unhurried on dynamic material where a similarly rated Class AB design starts to sound compressed.

Arcam A5+

The Arcam A5+ is the entry point, and it is a straightforward proposition: 50 watts per channel into 8 ohms from a Class AB output stage, an ESS ES9018 DAC, and a moving magnet phono stage that has been given proper attention rather than being bolted on as a tick-box feature.

Fifty watts is enough for most bookshelf and compact floorstanding speakers in a normal room. Distortion sits at 0.003 percent at 80 percent power, and the amplifier’s composure at higher levels is more noticeable than its raw output figure. Tonally it is the softest-edged model in the range, which makes it a sensible partner for brighter speakers or for anyone assembling a first proper system.

The “plus” designation refers primarily to the wireless side. Bluetooth 5.4 with Snapdragon Sound allows lossless streaming from compatible phones and tablets, and Auracast support means audio can be broadcast to multiple compatible headphones or speakers at once.

Key features:

• Class AB, 50 W per channel at 8 Ω (75 W at 4 Ω)
• ESS ES9018 DAC
• Moving magnet phono stage
• Three RCA line inputs, two coaxial, one optical
• Pre-out for adding a power amplifier or subwoofer
• Bluetooth 5.4 with Snapdragon Sound and Auracast
• 8.14 kg, 431 x 83 x 344 mm

Buy the Arcam A5+ at Premium Sound — £749

Arcam A15+

The Arcam A15+ adds 60 percent more power than the A5+, at 80 watts into 8 ohms and 120 watts into 4 ohms, along with a redesigned power supply and a distortion figure that drops to 0.002 percent.

That extra headroom changes the character more than the numbers imply. Bass gains weight and definition, and the amplifier holds its shape on complex passages where the A5+ begins to sound slightly polite. If your speakers are less efficient than around 88 dB, or your room is larger than a typical London sitting room, this is where the range starts to make sense.

The other significant addition is HDMI eARC. This lets the amplifier take audio directly from a modern television’s HDMI socket, including higher-bandwidth formats that optical cannot carry, and it means the TV remote controls the volume. For anyone who wants one system for music and television without adding a soundbar, eARC is the feature that makes it practical.

Key features:

• Class AB, 80 W per channel at 8 Ω (120 W at 4 Ω)
• HDMI eARC for television audio
• ESS ES9018 DAC
• Moving magnet phono stage, 47 kΩ + 100 pF input impedance
• Frequency response 20 Hz to 20 kHz ± 0.2 dB
• Bluetooth 5.4 with Snapdragon Sound and Auracast
• All-aluminium chassis, 10 kg

Buy the Arcam A15+ at Premium Sound — £1,199

Arcam A25+

The Arcam A25+ is the flagship of the Radia range and the first model in the line-up to use Arcam’s fifth-generation Class G topology. Output rises to 100 watts into 8 ohms and 165 watts into 4 ohms, with a signal-to-noise ratio of 106 dB on analogue inputs and 109 dB on digital.

The step up from the A15+ is not simply about volume. Class G gives the A25+ a noticeably firmer grip on the leading edge of notes, and low-frequency control improves in a way that becomes obvious on dense material. Difficult loads that make a Class AB design work hard are handled without the sound closing in.

Connectivity is the most complete in the Radia range. Alongside HDMI eARC, the A25+ adds a USB-C input supporting PCM up to 32-bit/384 kHz and DSD256, which makes it a genuinely capable partner for a laptop or music server. The phono stage remains moving magnet only, which is the main functional limitation if you are running a moving coil cartridge.

Key features:

• Fifth-generation Class G, 100 W per channel at 8 Ω (165 W at 4 Ω)
• ESS ES9018 DAC with enhanced power supply
• USB-C input supporting 32-bit/384 kHz PCM and DSD256
• HDMI eARC for television audio
• Moving magnet phono stage
• Signal-to-noise ratio 106 dB analogue, 109 dB digital
• All-aluminium chassis, 9 kg

Buy the Arcam A25+ at Premium Sound — £1,699

Arcam A50 Signature

Built to mark fifty years of Arcam amplifier design, the Arcam A50 Signature is the company’s first dual-mono Class G integrated amplifier, and the architecture is the story here.

Each channel operates as a self-contained amplifier: its own transformer windings, its own power regulation, its own reservoir capacitors, its own Class G lifter stage and its own output-stage heatsink. In effect there are two monoblocks sharing a chassis. The benefit is that neither channel can draw on the other’s supply during demanding passages, which is where shared-supply designs tend to lose stereo focus. On well-recorded material the result is a stage that stays organised at volume, with instruments holding their positions rather than smearing towards the centre.

Output is 150 watts into 8 ohms and 220 watts into 4 ohms. Digital conversion moves up to the ESS ES9039Q2M, with USB-C handling 32-bit/384 kHz and a digital signal-to-noise ratio of 109 dB.

The phono stage deserves particular mention. It is a Class A design supporting both moving magnet and moving coil cartridges, with careful attention paid to RIAA equalisation accuracy. Class A operation avoids the switching artefacts inherent to other topologies, which matters more here than almost anywhere else in an amplifier given the tiny signal levels a cartridge produces. There is also a proper headphone stage capable of driving a wide range of impedances, and balanced XLR pre-outs alongside the RCA set.

Key features:

• Dual-mono Class G architecture, 150 W per channel at 8 Ω (220 W at 4 Ω)
• ESS ES9039Q2M DAC, USB-C up to 32-bit/384 kHz
• Class A phono stage supporting MM and MC cartridges
• HDMI eARC for television audio
• RCA and balanced XLR pre-outputs
• Dedicated headphone stage
• Bluetooth 5.4 with aptX Lossless, LE Audio, Snapdragon Sound and Auracast
• 12 kg, 431 x 344 x 99 mm

Buy the Arcam A50 Signature at Premium Sound — £2,499

Arcam SA35

The Arcam SA35 is where the range changes shape. It is a complete streaming system: 120 watts per channel into 8 ohms and 200 watts into 4 ohms, built around a new six-layer digital audio and streaming board.

That board is worth explaining. A continuous ground plane runs across the full layer, routing noise and interference away from the sensitive analogue circuitry rather than letting it find its way into the signal path. The DAC is ESS’s Hyperstream IV architecture in a balanced configuration with jitter elimination, and the whole system is fed by a linear toroidal transformer. A secondary switching supply handles standby duties only, so it is not contributing noise during playback.

Streaming covers AirPlay, Chromecast, Spotify Connect, Tidal Connect and Roon, with Amazon Music, Qobuz, internet radio and podcasts accessible through the Arcam Radia app. Hi-res support extends to 32-bit/768 kHz. A bonded 6.5-inch display shows artwork and metadata legibly from a listening position.

The two features that matter most to system-building are the MM/MC phono stage and Dirac Live. Dirac measures your room using the supplied microphone and applies correction to the frequency and time-domain errors your room imposes, which in a typical rectangular British living room is often the single largest improvement available. Dual subwoofer outputs allow low-frequency support to be integrated properly rather than bolted on.

Key features:

• Fifth-generation Class G, 120 W per channel at 8 Ω (200 W at 4 Ω)
• Six-layer streaming platform with ESS Hyperstream IV DAC in balanced configuration
• Linear toroidal power supply
• AirPlay, Chromecast, Spotify Connect, Tidal Connect and Roon Ready
• MM and MC phono inputs
• HDMI eARC, two coaxial and two optical digital inputs
• Dirac Live room correction with measurement microphone included
• Dual subwoofer outputs
• 6.5-inch bonded high-resolution display
• Hi-res support to 32-bit/768 kHz, 12 kg

Buy the Arcam SA35 at Premium Sound — £2,999

Arcam SA45

The Arcam SA45 sits at the top of the range and inherits a good deal from the A49, Arcam’s previous flagship integrated. Power climbs to 180 watts into 8 ohms and 300 watts into 4 ohms, and the chassis weight rises to 17 kilograms, most of which is power supply and heatsinking.

The significant technical distinction is that the SA45 runs fully balanced analogue and digital signal paths. Balanced operation carries the audio as two inverted copies, so noise picked up along the way appears identically on both and cancels when the signal is recombined. It is why the format is standard in studios, and in a domestic system with long cable runs or a noisy mains environment the difference is audible as a quieter, more settled background. The SA45 provides an XLR input and XLR outputs, including balanced subwoofer outputs, alongside the usual RCA connections.

Everything else scales up rather than changes. The display grows to 8.8 inches, the Wi-Fi radio adds ax support, and the streaming platform, Dirac Live implementation and MM/MC phono stage carry over from the SA35. With 300 watts available into 4 ohms, this is the model to consider for genuinely demanding floorstanders or a large room.

Key features:

• Fifth-generation Class G, 180 W per channel at 8 Ω (300 W at 4 Ω)
• Fully balanced analogue and digital signal paths
• XLR input, XLR outputs and balanced subwoofer outputs
• Six-layer streaming platform with ESS Hyperstream IV DAC
• MM and MC phono inputs
• HDMI eARC, two coaxial and two optical digital inputs
• Dirac Live room correction with measurement microphone included
• 8.8-inch bonded high-resolution display
• Wi-Fi 802.11 a/b/g/n/ac/ax, 17 kg

Buy the Arcam SA45 at Premium Sound — £4,499

Two points are worth flagging before you decide. If you own or plan to own a moving coil cartridge, only the A50 Signature, SA35 and SA45 will accommodate it without an external step-up. And if your room is acoustically awkward, with hard floors, large windows or a pronounced bass mode, the Dirac Live models will often outperform a nominally more capable amplifier without correction.

If you would like help matching any of these to your speakers, our team is happy to talk it through.