Arcam A5+ Integrated Amplifier

Arcam built the A5+ as the entry point into their Radia+ range — but calling it entry-level slightly misrepresents what it does. Fifty watts per channel, 0.003% THD, lossless Bluetooth transmission, and a phono stage that most amplifiers at this price either omit or implement poorly — the A5+ arrives with a specification that competes well beyond its price point. If you are building a first serious two-channel system, or upgrading from a budget all-in-one, this is where Arcam's engineering starts making a genuine difference.

The Radia+ Range: Where the A5+ Sits

The Radia+ range runs across three integrated amplifiers: the A5+, the A15+ and the A25+. The step to the A15+ adds HDMI eARC — connecting your television directly into the amplifier — and 80 watts per channel. The A25+ moves to Class G topology and 100 watts, a more sophisticated amplifier design that runs more efficiently under normal listening conditions and draws on higher voltage reserves only when the music demands them.

The A5+ is the right choice when your room is a typical UK living room and your speakers are 86dB sensitivity or above. For most people building a first genuinely good system, 50 watts is enough — the A5+ does not sound strained at normal listening levels, and the 75 watts it delivers into 4Ω loads means it handles more demanding speakers with greater composure than the headline figure alone suggests. If HDMI eARC for TV integration is part of your brief, the A15+ is the answer. For large floorstanders or rooms over 25 square metres, the A25+ is worth the step up.

Sound Performance

The A5+ draws on Arcam's experience with Class AB amplification across nearly fifty years of British engineering. The 0.003% THD at 80% power into 8Ω reflects careful power supply design and signal path discipline — that figure is not typical for a £749 amplifier, and it has audible consequences.

One engineering detail worth knowing: the A5+ selectively powers down unused circuit modules — including the Bluetooth receiver and trigger inputs — when they are not in use. The aim is to reduce noise sources that are not contributing to the output. In practice this means a lower noise floor than you would expect at this price, and better low-level detail retrieval on quiet passages.

Soundstage on the A5+ is coherent and well-centred. Voices sit naturally, imaging is stable, and the frequency balance across the analogue inputs is neutral without being clinical. The Bluetooth implementation via aptX Lossless is genuinely lossless — a compatible source device transmits audio bit-for-bit identical to the original file, not an approximation of it. Auracast support adds multiroom broadcast capability, a feature that will become more relevant as Auracast-compatible devices become more common.

Build Quality and Engineering

The A5+ is built to the same physical standard across the Radia+ range: 431mm wide, 83mm high, 8kg. It fits on any standard equipment rack without difficulty, and the build quality — solid chassis, uncluttered front panel, quality terminals — reflects Cambridge manufacturing rather than cost reduction. At this price point the finish is noticeably better than most competitors.

The transformer and power supply have been upgraded from the previous generation of Arcam entry amplifiers. The phono stage is properly implemented: 47kΩ input impedance, RIAA accuracy within ±1dB. This is a phono stage you can use confidently with a good MM cartridge rather than one you will want to replace immediately.

Connectivity and System Matching

Three RCA line inputs handle analogue sources. Optical and coaxial digital inputs accept up to 192kHz/24-bit from CD players and other digital sources. The MM phono stage connects a turntable directly. A headphone output covers the 16Ω–2kΩ impedance range. No HDMI eARC — that begins with the A15+.

For sources, the A5+ pairs naturally with the Arcam ST25 network music streamer — shared Cambridge engineering, consistent presentation, and a tidy system stack. For physical media, the Arcam Radia CD5 connects via coaxial and keeps the Arcam aesthetic throughout.

On the speaker side, the A5+ works confidently with bookshelf speakers from 86dB sensitivity upward. KEF LS50 Meta, Bowers & Wilkins 606 S3 and Fyne Audio F300 are strong pairings at different price points. For large or inefficient floorstanders, the A25+ gives you more headroom without strain.

Technical Specifications

Who Is the A5+ For?

The A5+ suits the listener building a first serious two-channel system with a good pair of bookshelf speakers and a streamer or turntable. It also works well as a secondary system where sound quality matters but space is limited. If HDMI eARC for TV use is a requirement, the A15+ is the right starting point. If you are running large floorstanders or a room significantly over 20 square metres, the A25+ is worth the extra investment.

Buying from Martins Hi-Fi

Martins Hi-Fi has been in Norwich since 1968. Elizabeth Gould runs the business today, and we stock only brands we have heard properly and stand behind. Arcam have been a core part of our range for many years — Dave and Chris can talk you through whether the A5+, A15+ or A25+ is the right fit for your room and your speakers, and have it set up in our Norwich showroom for you to hear.

Contact us at info@martinshifi.co.uk, call 01603 627010, or WhatsApp on 07554 687137. You can read more about how we work on our Why Martins Hi-Fi page. We are at 85–91 Ber Street, Norwich, NR1 3EY.