Arc Ultra

Overview

Arc Ultra is the Sonos Dolby Atmos soundbar released in October 2024 as the successor to Arc. It is 1178 mm wide, 75 mm high and 110.6 mm deep, comes in black or white, and can stand on furniture or be wall-mounted.

Sonos describes 14 Sonos-engineered drivers driven by fifteen Class-D amplifiers. They include two upward-firing tweeters for the height channels and Sound Motion, a flat four-motor, dual-membrane woofer that Sonos introduced with Arc Ultra.

The TV connects over HDMI eARC with the included HDMI cable. An optical adapter is sold separately, and there is no built-in Ethernet port. Wi-Fi 6 connects Arc Ultra to the home network for the Sonos app, AirPlay 2 and Apple Music, and Bluetooth 5.3 streams from any Bluetooth device.

A far-field microphone array handles Sonos Voice Control and Amazon Alexa, and a switch on the back cuts power to the microphones. The top has capacitive touch controls, and Arc Ultra works with the TV remote. In the Sonos app you can adjust bass, treble and loudness, choose one of four Speech Enhancement levels and turn on Night Sound.

What the specs mean

• 9.1.4 speaker setup: nine main channels, one bass channel and four height channels, all from the single bar. A Sonos Sub, Sub Mini or Sub 4 adds a separate subwoofer, and a pair of Sonos speakers (One, One SL, Five, Era 100, Era 100 SL, Era 300) or IKEA Symfonisk Lamp (Gen 2) or Picture Frame speakers adds rear surrounds, all connected wirelessly.
• HDMI eARC: the enhanced Audio Return Channel carries the TV's sound to the soundbar over one HDMI cable, including high-bitrate formats such as Dolby TrueHD, Dolby Atmos and uncompressed multichannel audio. It also lets the TV remote control Arc Ultra.
• Audio formats: Dolby Atmos, Dolby Digital, Dolby Digital Plus, Dolby TrueHD, stereo PCM, multichannel PCM, Dolby Multichannel PCM and DTS Digital Surround. Sonos marks Dolby Atmos, Dolby TrueHD, multichannel PCM and Dolby Multichannel PCM as needing the HDMI eARC connection.
• No HDMI passthrough: Arc Ultra has no HDMI input, so a console or streaming box connects to the TV, and the TV sends the sound on to Arc Ultra over eARC.
• Room correction (Trueplay): Trueplay measures the room's acoustics and tunes the soundbar's EQ. For Arc Ultra, Sonos supports Trueplay tuning from both iOS and Android devices.