Arcam ST25 Network Music Streamer

The Arcam ST25 is the reference-level streaming source in the Arcam range — a standalone network player built around the ESS Hyperstream IV DAC in balanced configuration, with a linear toroidal power supply, a six-layer digital audio platform, support for 32-bit/384kHz PCM and DSD256, and Roon Ready certification with a two-year Roon subscription included. This is the streaming source for listeners who take the digital front end seriously rather than treating it as an afterthought.

Where the ST25 Sits in the Arcam Streamer Range

The Radia ST5 is the streaming source for the Radia integrated amplifier range: an ESS ES9018 DAC, 24-bit/192kHz, DSD128 and a control link designed for the Radia amplifiers specifically. The ST25 is the step up in every technical respect: the ESS Hyperstream IV DAC (the same converter used in the SA35 and SA45 streaming amplifiers), 32-bit/384kHz PCM, DSD256, a 6.5-inch colour display, a linear toroidal power supply and a six-layer digital platform designed from the ground up for the HDA range.

The ST25 pairs naturally with an integrated amplifier via coaxial or optical, and with the SA35 or SA45 for listeners who want a dedicated streaming source feeding an all-in-one streaming amplifier. In that configuration the ST25 bypasses the SA35/SA45's internal streaming platform and feeds directly into the analogue or digital input — an approach some listeners prefer for its source separation.

Sound and Performance

The ESS Hyperstream IV is ESS Technology's current reference DAC topology — a higher specification design than the ES9018 in the ST5. The balanced differential signal path within the ST25 provides common-mode noise rejection from conversion through to the analogue outputs, keeping the noise floor below what the listening environment imposes rather than what the electronics allow.

The linear toroidal power supply distinguishes the ST25 from most streaming sources at any price. Switch-mode power supplies are efficient and compact but introduce high-frequency noise that can couple into sensitive audio circuitry. A linear supply with a toroidal transformer operates cleanly and quietly; the ST25 uses this rather than a compact adapter for reasons of sound quality rather than cost management.

Roon Ready certification means the ST25 appears as an audio zone within a Roon setup, with full metadata, radio and playback management through the Roon interface. The two-year subscription makes this immediately usable rather than a theoretical capability. For listeners not using Roon, Spotify Connect, Tidal Connect, Qobuz Connect, AirPlay, Google Cast, internet radio, UPnP and USB media cover every other major source.

Build Quality and Design

The ST25 is built in anodised aluminium to the same standard as the SA35 and SA45 — the same Cambridge engineering approach in a chassis designed to sit alongside the amplifiers it feeds. At 432 × 329 × 99mm and 5kg it is a compact unit, and the 6.5-inch colour display shows album art and streaming information clearly. The six-layer digital audio platform is a new design developed specifically for this product rather than an adapted off-the-shelf streaming board.

Connectivity and System Matching

One stereo RCA analogue output pair, one coaxial digital output (RCA) and one optical Toslink cover all standard connection options. Wi-Fi (802.11 a/b/g/n/ac/ax, dual-band) and Ethernet provide network connection. USB-A supports media playback from external storage.

Technical Specifications

Who Is the ST25 For?

The ST25 suits the serious listener who wants the best streaming source Arcam make in a standalone chassis — whether to pair with an A25+ integrated amplifier, as a dedicated source feeding an SA35 or SA45, or as the streaming component in a system that already has physical sources covered. If you are using Roon, the included two-year subscription makes the ST25 particularly good value at its price. If the Radia control link and a lower price point are your priorities, the ST5 remains the right Arcam streamer.

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 ST25 or the Radia ST5 is right for your system, and have it set up in our Norwich showroom for you to hear.

Contact us at [email protected], 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.