Polk Audio Signa S4 Soundbar and Wireless Subwoofer

The Polk Audio Signa S4 is a Dolby Atmos certified 3.1.2 channel soundbar and wireless subwoofer system from Polk’s Signa series. Designed at Polk’s Acoustic Research and Development centre outside Baltimore, the S4 sits at the top of the Signa range, adding Dolby Atmos height channels and a dedicated centre channel driver to the proven Signa platform.

Driver Array and Atmos Height Channels

The soundbar houses a seven-driver array arranged as a 3.1.2 configuration. Left and right channels each have a 25mm tweeter and a 120mm × 40mm racetrack midrange driver, providing wide stereo separation. A dedicated 25mm full-range centre channel driver handles dialogue independently of the left and right channels. Two upward-firing 66mm elevation drivers bounce sound off the ceiling to create the overhead height layer that Dolby Atmos soundtracks use for three-dimensional audio placement.

Wireless Subwoofer

The included wireless subwoofer connects automatically and can be placed up to 10 metres from the soundbar. It houses a 150mm driver in a ported enclosure, providing low-frequency extension without running cables across the room. Bass Adjust controls low-frequency output on both the soundbar and subwoofer simultaneously, allowing the balance to be tuned to the room.

VoiceAdjust and Sound Modes

Polk’s patented VoiceAdjust technology works with the dedicated centre channel to raise the volume of dialogue independently of the rest of the soundtrack. Three preset sound modes are available via the remote: Movie mode optimises the surround field for film and television, Music mode adjusts the tonal balance for stereo content, and Night mode attenuates bass output while accentuating dialogue clarity for late-night viewing.

Connectivity

A single HDMI eARC connection carries Dolby Atmos, Dolby TrueHD, Dolby Digital Plus, Dolby Digital, and multichannel Linear PCM from the television. An optical TOSLINK input and a 3.5mm analogue auxiliary input provide fallback connections for older televisions or source components. Bluetooth allows wireless music streaming from mobile devices. A USB-A port is included for firmware updates. The soundbar is pre-programmed to respond to most television remote controls straight out of the box.

Design and Installation

The low-profile soundbar measures 1046mm wide, 95mm deep, and just 60mm tall, designed to sit in front of a television without blocking the screen or the TV’s IR remote sensor. A wall-mount template and spacers are included for fixed installation. The system ships with both an HDMI cable and an optical cable, so no additional purchases are needed for setup.