Premiera Goes All-In on Class AB With the 275W A5 Axiom

Premiera is taking a decidedly traditional approach to high-powered amplification with the A5 Axiom, a substantial Class AB integrated amplifier combining a dual-mono power stage with modern digital connectivity, an ESS Sabre DAC, HDMI ARC, MM/MC phono support and bidirectional Bluetooth.

Rather than moving toward the increasingly common Class D architecture, the A5 Axiom is built around separate power supplies for its left and right channels and is rated to deliver 170 watts per channel into 8 ohms, rising to 275 watts per channel into 4 ohms.

That puts the A5 Axiom firmly into high-power integrated-amplifier territory, but Premiera has also equipped it to function as the center of a considerably more complicated hi-fi system.

275 Watts Per Channel From a Dual-Mono Class AB Design

At the heart of the A5 Axiom is a dual-mono Class AB amplifier architecture in which the two channels receive independent power supplies.

Internally, each channel uses its own Custom Audio Grade transformer and rectification stage with four 10,000µF filtering capacitors. The output stages use three complementary pairs of bipolar power transistors per channel.

Premiera specifies output at 2 x 170 watts into 8 ohms and 2 x 275 watts into 4 ohms. The claimed damping factor is greater than 350 at 8 ohms and 100Hz, while the stated frequency response extends from 10Hz to 58kHz within ±0.5dB.

Channel separation is specified at greater than 98dB and the signal-to-noise ratio at more than 107dB. THD+N is quoted at below 0.08% across the amplified frequency range when delivering 150 watts per channel into 8 ohms.

Those numbers make the A5 Axiom considerably more ambitious than a conventional midrange integrated amplifier.

ESS ES9038Pro DAC Handles 32-bit/768kHz PCM

The digital section is based around ESS Technology silicon.

Digital-to-analog conversion is handled by the eight-channel ESS Sabre ES9038Pro using the company’s HyperStream II architecture. Premiera specifies support for PCM playback up to 32-bit/768kHz along with DSD256 via DoP.

Interestingly, there is also an ESS ES9826 32-bit ADC inside the amplifier. This allows analog signals to be digitized where required by the A5 Axiom's internal architecture.

Despite the considerable amount of digital technology onboard, volume adjustment itself remains analog. The control operates across a claimed -111.5dB to 0dB range in 0.5dB increments using a ladder-type circuit.

Premiera has also retained proper analog tone controls rather than relying entirely on DSP. Bass, midrange and treble can each be adjusted by ±10dB, while a Tone Defeat function bypasses the controls when they are not required.

HDMI ARC Makes the A5 Axiom TV-Friendly

Connectivity is one of the more unusual aspects of the A5 Axiom.

Alongside conventional hi-fi sources, the amplifier includes HDMI ARC, allowing audio from a television to be routed directly through a stereo system without requiring a separate AV receiver.

The digital input selection also includes two Toslink optical connections, coaxial S/PDIF, USB Audio and professional AES/EBU.

For analog equipment there are five RCA line-level inputs together with three XLR connections, depending on configuration. Premiera has also included a dedicated MM/MC phono stage, allowing moving-magnet and moving-coil cartridges to be connected directly.

There is additionally a monitor input that can route a signal directly into the amplification chain, giving the A5 Axiom some functionality that is increasingly unusual on modern integrated amplifiers.

Bluetooth 5.4 Works in Both Directions

Wireless connectivity comes through Bluetooth 5.4, but Premiera has implemented the connection in both receive and transmit modes.

The codec list is extensive and includes aptX, aptX HD, aptX Adaptive, aptX Low Latency, aptX Lossless, LDAC and AAC.

Receive mode works in the expected way, allowing music to be played from a smartphone, tablet or computer.

More unusually, transmit mode allows audio from sources connected to the amplifier to be sent onward over Bluetooth. That means a source connected through one of the A5 Axiom's analog or digital inputs can potentially be listened to through compatible wireless headphones.

There is also a dedicated slot at the rear of the amplifier designed to accommodate an optional streaming module, providing an upgrade route for users wanting integrated network playback.

Plenty of Outputs for Larger Hi-Fi Systems

Premiera has not treated the A5 Axiom as a closed integrated amplifier.

Preamp outputs are available on both RCA and XLR, allowing an external power amplifier to be added. There are also RCA and XLR recording outputs and corresponding mono subwoofer outputs.

A Toslink digital output is included as well.

For headphones, the front panel carries a conventional 6.3mm connection, while two sets of speaker terminals allow users to connect separate speaker pairs or configure compatible loudspeakers for bi-wiring.

Trigger connections and external IR control are included for more complex system installations.

Altogether, it is a connection set more reminiscent of a combined preamplifier, DAC and power amplifier than a minimalist modern integrated.

Large Analog Meters Dominate the Front Panel

Visually, the A5 Axiom does not attempt to hide its traditional hi-fi influences.

Two large analog power meters occupy much of the front fascia and display RMS output level across a scale running from -50dB to +5dB.

Users can independently alter the illumination intensity of the meters, display and controls, while the meter illumination itself can be switched between orange, green and white.

The amplifier is available with a conventional black front panel along with limited gold-finished versions using either black or white meter faces.

At 434mm wide, 195mm high and 423mm deep, this is also a physically imposing amplifier. Weight is listed at 20.1kg, while maximum power consumption can reach 1000W.

An Integrated Amplifier Built Against the Current Trend

The A5 Axiom arrives at an interesting point for integrated amplifier design.

A growing number of high-output amplifiers have moved toward compact Class D platforms, often combining switching amplification with highly integrated streaming electronics. Premiera has instead built a large Class AB amplifier around separate channel power supplies, substantial conventional output stages and physical analog controls, before adding contemporary digital functionality around it.

That creates an unusual combination.

There is an ES9038Pro DAC and support for 768kHz PCM, but also an MM/MC phono stage. There is HDMI ARC for a modern television alongside AES/EBU for professional digital equipment. Bluetooth supports aptX Lossless and LDAC, yet the front panel is dominated by traditional illuminated power meters.

Most importantly, the connectivity does not come at the expense of amplifier output: the A5 Axiom remains a 170-watt-per-channel design into 8 ohms and is rated for 275 watts per channel into 4 ohms.

For listeners who want modern source flexibility without abandoning the size, power reserves and architecture of a traditional Class AB integrated amplifier, the Premiera A5 Axiom is one of the more unusual new designs to emerge in this category.