Arcam Radia A5 Plus vs A15 Plus vs A25 Plus: Which Integrated Amplifier Fits Your System

Introduction

Arcam’s Radia range arrived in 2023 with a new design language and a clear good, better, best structure across its integrated amplifiers. The Radia Plus models continue that story rather than restarting it. The A5 Plus, A15 Plus, and A25 Plus keep the dark metalwork and subtle yellow trim that made the series recognisable, and they add meaningful updates: Bluetooth 5.4, a dedicated moving magnet phono stage on every model, and HDMI eARC on the two larger amplifiers.

That restraint is worth understanding before you buy. Arcam did not rebuild a platform that already worked. Instead, the Plus series targets the details people notice over years of ownership: quieter backgrounds, more readable displays, more flexible connections, and smarter power management.

What Carries Over and What Changes

Every Radia Plus amplifier keeps the chassis that defined the series. The curved rear cowl still hides antennas and cables, the knobs retain their satisfying weight, and the whole assembly feels solid and premium without being flashy. The OLED displays now offer better contrast and readability than the previous generation.

The front panels are where the three models separate visually. The A5 Plus and A15 Plus use a frosted front panel that gives the series its signature soft glow, while the A25 Plus moves to a precision cut glass front for a deeper, more high-end appearance. That finish also makes it a natural visual partner for the ST25 streamer.

Bluetooth is the other headline change. All three amplifiers step up to Bluetooth 5.4 with Snapdragon Sound, LE Audio, and Auracast, replacing the 5.2 module in the original models. Compatible Android devices can achieve bit perfect CD quality playback over Bluetooth, iPhone users still get solid performance through AAC, and Auracast opens up new ways to listen by sharing music to multiple Bluetooth headphones or speakers at once. Because the module is two-way, you can stream music to the amplifier or send audio out to wireless headphones for private listening. Bluetooth is ideal for quick playback when guests arrive, and Arcam’s dedicated streamers such as the ST5 or ST25 remain the better route for critical listening.

Arcam Radia A5 Plus: The Entry Point

The A5 Plus remains the entry point of the lineup, and it benefits from a refined power supply and an improved circuit layout that reduce interference and crosstalk. It is still a 2x50W class AB design into 8 ohms with an ESS ES918 DAC, but the result is a quieter background and better control over low-level dynamics, giving it noticeably more poise than before.

In practical terms, this is an amplifier for a medium to smaller room paired with reasonably easy to drive speakers. It keeps the full Radia Plus feature set, including the moving magnet phono stage and the upgraded Bluetooth module, and it pairs neatly with a dedicated Arcam streamer.

Arcam Radia A15 Plus: The Living Room Model

The A15 Plus sits in the middle of the range, delivering 2x80W into 8 ohms from the same class AB design and the same ESS ES918 DAC. Arcam reworked the transformer to smooth current delivery and improve control, which helps the amplifier sound more open and natural at lower listening levels. Vocals and instruments stay clear and stable even when the volume is turned well down.

The addition of HDMI eARC is what makes this model genuinely versatile. A single HDMI cable connects the amplifier directly to a television, turning a hi-fi system into the main entertainment hub for the home. You can watch a film, a series, or play a game and hear everything through proper speakers, using the TV remote to change volume. Compared with built-in TV speakers or a soundbar, a stereo amplifier and two dedicated speakers deliver a far more convincing result.

This is the model that makes sense for a very broad range of people, because it combines the full feature set with enough power for typical living rooms. Paired with an ST5 or ST25 streamer, it forms a system that punches well above its position in the range.

Arcam Radia A25 Plus: The Class G Flagship

The A25 Plus leads the lineup and keeps Arcam’s fifth generation class G design, but almost every part of the power supply has been re-engineered. The DAC has changed to the ES918 in this new model, and Arcam added a dedicated DAC winding, doubled linear regulation on the analog rails, and improved filtering for a cleaner and more stable platform. Rated output remains 2x100W into 8 ohms, with a presentation that comes across as smoother, more open, and more controlled.

Class G is the technology that separates this model from the rest. Rather than the traditional class AB approach used in the A5 Plus and A15 Plus, class G uses multiple power rails and draws extra voltage only when the music demands it. The A25 Plus runs in pure class A for the first 15 watts, delivering rich, distortion-free sweetness and micro detail, then switches automatically to higher rails for dynamic passages without strain. The result is efficiency, refinement, and the unmistakable Arcam warmth from quiet listening through to full volume.

Connectivity also reaches furthest here. The A25 Plus adds a USB-C input supporting high resolution playback up to 32-bit 384 kHz, which is ideal for connecting a laptop or smartphone over a direct, stable signal path. Its optical and coaxial inputs are limited to 24-bit 192 kHz. Combined with the precision cut glass front, it is the model to choose when you want the top of the range.

Connectivity and Everyday Listening

Vinyl listeners are well covered, because every amplifier in the Radia Plus lineup includes a dedicated moving magnet phono stage. You can plug a turntable straight in without an external preamp, and the stage is built with the same attention to low noise and wide dynamic range as the rest of the circuit, delivering a warm, detailed sound that brings records to life.

Each model also includes three RCA analog inputs and a preamp output for adding a subwoofer or an external power amplifier. For digital sources there are optical and coaxial inputs, plus a service USB-A port, Ethernet, IR in, and 12V trigger connections for system integration. Every model has a 3.5 mm headphone jack on the front panel, and the A15 Plus and A25 Plus add HDMI eARC.

If you want the best possible sound from streaming, adding one of Arcam’s dedicated streamers such as the ST5 or ST25 is the recommended path. Bluetooth remains the convenient option, while a dedicated streamer handles serious listening.

Power Management and Long-Term Ownership

The Plus series also benefits from smarter power management. The DAC powers down automatically when an analog input is selected, and the Bluetooth and HDMI modules shut off when their auto switch features are disabled. Those auto switch features ship enabled, which is convenient because the amplifier follows the input you are using. If you want the very best performance, you can turn them off manually.

These steps may sound minor, but they contribute to a lower noise floor and better long-term reliability. It is also worth noting that nothing was lost from the original Radia series. Owners of the first generation models can rest easy, because those amplifiers remain fully current in sound quality and core performance. The Plus series simply builds on the same foundation.

Choosing the Right Radia Plus Amplifier

The decision comes down to room size, speaker demands, and how your system is used. The A5 Plus is the sensible starting point for a smaller to medium room with easy to drive speakers, and it delivers the same phono stage, Bluetooth feature set, and build quality as its larger siblings.

The A15 Plus is the balanced choice for most people. Its 80W per channel and reworked transformer suit typical living rooms, and HDMI eARC makes it the natural centre of a system that handles both music and television. If films and shows matter as much as albums, this is the model to shortlist first.

The A25 Plus is for listeners who want the flagship experience: class G amplification with the first 15 watts in pure class A, 100W per channel, a USB-C input supporting up to 32-bit 384 kHz, and the precision cut glass front. It is the most capable amplifier of the three and the one that pairs most naturally with the ST25 streamer.

Whichever model you choose, the fundamentals are consistent across the range: a moving magnet phono stage, three RCA inputs, a preamp output for a subwoofer or external power amp, optical and coaxial digital inputs, Ethernet and trigger connections, a front headphone jack, and Bluetooth 5.4 with Snapdragon Sound, LE Audio, and Auracast.

Conclusion

The Radia Plus series feels less like a reboot and more like a continuation of a story that started well. Arcam kept the design and the proven platform, then added the updates that matter: better displays, a more capable Bluetooth module, a phono stage on every model, HDMI eARC on the A15 Plus and A25 Plus, and a thoroughly reworked flagship in the A25 Plus.

If you are building a new system, match the amplifier to your room and your speakers rather than to the spec sheet alone. The A5 Plus rewards a modest, well-matched setup, the A15 Plus covers music and movies with genuine flexibility, and the A25 Plus delivers the fullest version of what the range can do.