Arcam SA45 Streaming Amplifier

Introduction

The Arcam SA45 is a highly anticipated flagship streaming integrated amplifier, representing the latest evolution in Arcam's audio solutions. It features a significant brand redesign, offering a more modern aesthetic and enhanced functionality compared to previous generations.

The Arcam SA45 features a prominent 8.8-inch (224mm) full-colour display on its front panel. This display shows album artwork, chosen input, internet radio presets, and other metadata. The unit has a black casework with distinctive yellow accents, including around the large rotary volume knob and source selection dial.

Priced at £4500, the SA45 is positioned as a premium offering, aiming to provide a compelling combination of features, performance, and style.

Design and Features

The SA45 showcases Arcam's new 'brand redesign', moving away from its previous conservative styling. The new look includes black casework accented with eye-catching yellow flourishes on both the amplifier and its bundled remote control. A key visual element is the large 8.8-inch (224mm) full-colour display, a first for Arcam, which brings it in line with competitors from NAD, Naim, and HiFi Rose.

An internal view reveals a substantial toroidal transformer located at the top right, powering the Class G power supply and amplifier section. Multi-layer printed circuit boards (PCBs) are visible, hosting components such as the network module, HDMI eARC input, ESS ES9027SPro DAC, MM/MC phono stage, line inputs, and isolated preamp outputs.

Internally, the SA45 utilizes Arcam's 5th generation Class G amplification, rated at 2x180W into 8 ohms. This technology uses multi-rail power supplies that are introduced according to signal demand, with higher rails engaged only when audio output exceeds a certain level. Arcam's refined version ensures smooth tracking of audio levels rather than abrupt switching.

The amplifier supports extensive digital audio and streaming capabilities. It includes Qobuz Connect, Tidal Connect, and Spotify Connect, alongside Apple AirPlay and Google Cast (with Roon certification pending). File handling supports up to 384kHz/32-bit PCM and DSD512, processed by an ESS DAC on a new six-layer board with fully balanced analogue circuitry. A new linear power supply with a toroidal transformer complements the design.

Connectivity is comprehensive:

• MM and MC phono inputs
• 3x RCA and 1x balanced XLR analogue line inputs
• Preamp outputs (RCA and XLR)
• 2x optical and 2x coaxial digital inputs
• USB-A for playback from storage devices
• HDMI eARC
• Ethernet socket for network connection
• Wi-Fi and two-way aptX Bluetooth (for headphones)

The rear panel offers comprehensive connectivity. It includes separate MM/MC phono inputs, four line inputs (one balanced on XLR), two preamp and filtered sub outputs (RCA and XLR), with digital on two optical, two coaxial, USB-A and HDMI eARC. Bluetooth 5.4 is supported alongside Wi-Fi and wired Ethernet (up to 384kHz/32-bit), and note the pairs of chunky 4mm speaker sockets.

User Interface and App

The SA45 features a high-definition 8.8-inch display that is not a touchscreen. User settings include choices for digital filters, display dimming, and illumination around control knobs. Input 'hiding', balance, and maximum volume can also be adjusted.

The Arcam Radia app, available for iOS and Android, serves as a user interface for music selection and network setup. It is described as slicker than Arcam's previous MusicLife app. The app displays icons for Presets, Radio, Qobuz Connect, Spotify, UPnP, and USB. It also provides access to a settings page for firmware updates, network status, Google Cast settings, and device renaming. While it facilitates music browsing and playback control, it does not manage input selection, digital filter choices, or Dirac profile adjustments, which require the front panel or remote.

For Internet Radio, the SA45 uses the Airable platform, allowing browsing by genre, language, and location, with options to mark favourites and set up six presets.

Sound Quality and Performance

The SA45's sound performance is noted for its purposeful and powerful character, reminiscent of previous top-flight Arcam amplifiers. It delivers significant 'grunt' with excellent grip and depth in percussion and basslines. The amplifier maintains this solidity across the audioband, providing a listening experience with plenty of body and heft.

The sound profile is described as a 'crowd-pleaser', balancing detail with an inviting, neutral tonality. It handles a wide range of music genres effectively, from pop artists like Taylor Swift to classical composers like Tchaikovsky. The amplifier is praised for its ability to reproduce intricate details, such as tinkling percussion and pizzicato violins, while also delivering impactful bass.

The Class G amplification is noted for its ability to provide extra power when needed, particularly during demanding bass passages. Examples cited include the basslines in Nas's 'N.Y. State Of Mind' and the low-end reproduction from B&W 705 S3 Signatures speakers.

The digital stage is described as admirable, offering focused and detailed sound. While not reaching the absolute airy highs of dedicated digital solutions, it provides a cohesive and revealing experience, particularly in the high frequencies.

The SA45's comprehensive connectivity and app control make it versatile for various sources. It is capable of handling diverse musical styles, from hip-hop and rock to blues and easy listening, with clarity and impact.

Dirac Live Room Correction

A key feature is Dirac Live Room Correction, a third-party calibration platform. The SA45 includes a microphone and instructions for downloading the necessary software and calibration files. While the process can be time-consuming and potentially complex for novices, it is capable of producing significant improvements in sound quality by optimizing the system for room acoustics and speaker placement.

The SA45 also supports Dirac's Bass Control tool for enhanced subwoofer integration and offers dual outputs for subwoofers on both unbalanced RCA and balanced XLR connections.

Lab Report and Specifications

The laboratory report confirms the SA45's impressive technical capabilities:

• Power Output: Rated at 198W/8ohm and 323W/4ohm (<1% THD).
• Dynamic Power: Delivers 255W/8ohm, 475W/4ohm, 805W/2ohm, and 745W/1ohm under dynamic conditions.
• Distortion: Extremely low, measured at 0.0004-0.0009% over its rated range (1kHz/8ohm) and 0.0003-0.0014% (20Hz-20kHz/10W/8ohm).
• Noise and S/N Ratio: Very low noise with a wide 96dB A-wtd S/N ratio (re. 0dBW) for the amplifier section and 111.4dB for the DAC section.
• Frequency Response: Flat to -0.17dB within 20Hz-20kHz, extending to -6.05dB at 100kHz.
• Output Impedance: Low, ranging from 0.09ohm to 0.053ohm (20Hz-20kHz).
• Digital Performance: Jitter is extremely low (<5psec), and distortion is minimal (0.0002-0.0014% for DAC).
• Power Consumption: 54W idle, 565W at rated output, 1W standby.
• Dimensions: 432mm (W) x 140mm (H) x 390mm (D).
• Weight: 17kg.

Graph 1 illustrates the dynamic power output versus distortion into various speaker loads (8ohm, 4ohm, 2ohm, 1ohm). It shows that the amplifier can deliver significantly more than its rated 180W/8ohm under dynamic conditions, reaching up to 805W into 2ohm loads, with a maximum current of 27.3A.

Graph 2 displays distortion versus digital signal level over a 120dB range for 48kHz/24-bit digital input, measured at 1kHz (black trace) and 20kHz (blue trace). It highlights extremely low distortion levels, often below 0.0003% across the tested range.

Verdict

The Arcam SA45 is lauded as a fine standard-bearer for Arcam's refreshed hi-fi lineup and aesthetic. It is recognized as the company's most stylish and well-connected amplifier to date. The integrated unit feels thoroughly modern in both its design and execution. Sonically, it is described as a chameleon, capable of powerful, headbanging sound one moment and soothing, detailed playback the next, all while adapting effectively to the listening environment through its Dirac software.

Sound Quality: 88%