Class G Amplifiers and the New Shape of High-End Power
Class G amplifiers are high-fidelity power amplifiers that switch between multiple supply rails, improving efficiency over traditional Class AB designs while keeping distortion low and heat output manageable, which makes them attractive for high-end audio systems that must deliver both serious power and practical everyday operation. At High End Vienna, that design philosophy framed a broader shift in power amplifier design: high-performance brands are now expected to unite classic circuit craft with streaming amplifier features and custom-install flexibility. ARCAM, Cambridge Audio and Chord Electronics each arrived with integrated amplifier debuts or new stereo power amplifiers that answer this demand from different angles. One recurring theme was efficiency—not just in power consumption, but in how these products fit into modern systems, from living-room streaming hubs to rack-mounted architectural audio. The result is a new generation of amplifiers that treat network audio and installation needs as core requirements, not bolt-on extras.
ARCAM’s A50 Signature: Dual-Mono Class G for a 50th Anniversary
ARCAM used High End Vienna to mark its 50th anniversary with the A50 Signature integrated amplifier and CD25 CD player, both extending the Radia Series. The A50 Signature is the company’s most advanced integrated amplifier to date and its first to adopt a fully dual mono Class G architecture, with separate PCBs, output stages, Class G lifter stages and power regulation for each channel. According to ARCAM, co-founder John Dawson was directly involved to ensure the amplifier reflects the firm’s long-standing design philosophy while addressing how people listen today. This ties the A50 back to the classic A60, but the focus now includes digital connectivity and system integration alongside Class G efficiency. The matching CD25, a new flagship CD player, confirms ARCAM still takes physical media seriously, positioning the pair as a modern answer for listeners who want traditional silver-disc playback and integrated amplification without sacrificing contemporary connectivity or control options.
Cambridge Audio Evo 300: Streaming Amplifier Muscle with 300W per Channel
Cambridge Audio’s Evo 300 pushes the Evo Series into heavyweight territory as a streaming amplifier built around Hypex NCOREx Class D power. Rated at 300 watts per channel into 8 ohms in a dual mono layout, it is positioned as Cambridge’s most powerful and sonically advanced Evo yet, targeting larger rooms and more demanding loudspeakers without resorting to a bulky heat-sinked chassis. The amplifier includes a balanced preamplifier stage and dedicated analog volume controls for each channel to preserve imaging, dynamics and low-level detail. On the network side, StreamMagic Gen 4 provides access to Spotify Connect, TIDAL Connect, Qobuz Connect, Amazon Music, Deezer, UPnP, internet radio and Roon Ready operation, over Ethernet or Wi-Fi. Cambridge acknowledges earlier concerns about StreamMagic stability, but recent updates and distributor changes indicate renewed focus on software. Together, this makes the Evo 300 an integrated amplifier debut that combines serious Class D power, streaming flexibility and everyday practicality in a single box.
Chord Electronics ULTIMA 7 and Blade: Class G Power for Racks and Rigs
Chord Electronics used the show to preview two new stereo power amplifiers ahead of their formal autumn release: the ULTIMA 7 and Blade. Both are British-made, designed by founder John Franks and built around Chord’s ULTIMA amplifier technology, signaling that the company’s analog ambitions stand alongside its well-known DACs. The ULTIMA 7 becomes the most affordable full-width power amplifier in Chord’s lineup and is designed to match the ULTIMA PRE 3 preamplifier visually, delivering 135 watts per channel into 8 ohms. More radical is Blade, a slimline 0.5U Class G GaN stereo amplifier aimed at the custom installation market. Its low-profile form factor is tailored for racks and architectural audio, where efficient, cool-running power matters as much as sound quality. By bringing Class G and gallium nitride devices into a CI-friendly chassis, Chord positions Blade as a bridge between high-end listening rooms and hidden whole-home audio systems.
Efficiency, Streaming and Architecture: A Converging Future for High-End Amplifiers
Taken together, ARCAM’s A50 Signature, Cambridge Audio’s Evo 300 and Chord Electronics’ ULTIMA 7 and Blade trace a clear direction for high-end audio. Amplifiers are no longer judged only on watts, topology or finish; they must also fit into streaming-led ecosystems and, increasingly, into architectural audio and custom installation frameworks. Class G amplifiers and advanced Class D platforms such as Hypex NCOREx allow brands to deliver high power with less heat and size, while dual mono layouts and balanced stages keep audiophile credibility intact. Streaming amplifier designs like Evo 300 treat software platforms as critical components, while products like Blade address installers who need slim, rack-ready power that still carries a high-fidelity badge. For listeners and integrators, the message from this high-end audio show is clear: efficiency, flexibility and integration now stand alongside pure sound quality as equal priorities in modern power amplifier design.
