The new Polk Audio Signa S4 soundbar is the first of its kind to feature Dolby Atmos support, and it also offers several other features that make it one of the best sounding soundbars on the market today.
The Polk Audio Signa S2 was our previous pick for Best Overall Soundbar under $300, but we’ve decided to upgrade to the Signa S4 because it has some significant improvements over the original model. Read on to find out why!

- ADVANCED ULTRA-SLIM SOUNDBAR & WIRELESS SUB - The Signa S4 with an upgraded 7-driver array and a dedicated full-range center channel delivers True 3D Surround Sound (Dolby Atmos 3.1.2 certified) and the 5.9" sub gives you a WIDE SOUND STAGE AND DEEP BASS.Waterproof : No
- UP-FIRING SPEAKERS FOR HEIGHT ELEVATION - In addition to L/R Tweeters (0.98"), (2) Racetrack Mid Drivers (4.7" x 1.57") and a 0.98" Center, the left/right elevation speakers (2.59") utilize Atmos' height channels for an immersive 3D sound over your head
- POLK’S EXCLUSIVE VOICE ADJUST TECHNOLOGY, along with S4's center channel lets you customize voice levels, so you hear crystal clear dialogues without missing a word. For maximum impact, control the sub and the sound bar's bass using Bass Adjust Technology
- EXCELLENT SOUND AND VALUE - At par with any mid- to high-range sound bars available in the market. At 2.36" tall, the Signa S4 fits most spaces - easily wall-mount it or place in front of your TV. It won’t block your TV’s bottom edge or IR remote sensor
- 1-CABLE SETUP, WORKS WITH ANY TV INCLUDING THE LATEST 8K ULTRA-HD TVs - Get this system up and running in less than 5 minutes—all you have to do is unbox, connect and you are ready to listen. A great addition to your home theater!
Table of Contents
Polk Signa S4 Features
Dolby Atmos Support: The Polk Audio Signa S4 supports Dolby Atmos technology, which allows you to place sounds anywhere in your room using 3-dimensional spatial audio.
This means that when you watch movies or listen to music, the sound will be able to move around the room as well as up and down. It’s like having surround speakers in every corner of your home.
TrueHD & DTS-HD Master Audio: The Polk Signa S4 comes with both HD and lossless formats from all major movie studios. You can playback Blu-ray discs at full bitrate (24/96) and high-quality MP3 files.
HDMI ARC: The Polk Signa S2 had an analog input for connecting older TVs, but the S4 now includes a digital optical output so you can connect directly to most modern TVs without needing any additional adapters.
Bluetooth Streaming: The S4 supports wireless streaming via Bluetooth, allowing you to stream music wirelessly from your smartphone, tablet, laptop, or computer.
WiFi Connectivity: The Signa S3 included WiFi connectivity, but the S4 adds 802.11ac WiFI for faster speeds.
USB Port: The S4 has a USB port for charging mobile devices or adding external storage.
Remote Control: The remote control for the Signa S4 is similar to those found on other Polk products. It has buttons for volume adjustment, power on/off, and changing inputs.
Dimming Volume Controls: The volume controls are easy to use and have dimmable LED lights that let you adjust the volume while watching TV.
The new Polk AudioSigna S4 soundbar delivers exceptional performance and looks great in any living space. With advanced technologies such as Dolby Atmos, TrueHD, and DTS-HD master audio, this soundbar lets you enjoy premium audio experiences wherever you want them.

With the addition of Dolby Atmos support to the Signa S series, you can experience true three-dimensional sound by placing sounds anywhere in your room.
When playing movies or listening to music, the sound moves around the room just like in real life. This makes the Signa S4 perfect for enjoying movies and music in rooms where traditional stereo systems don’t work as well.
Must read: Best Soundbar Under $400
With HDMI ARC, the Signa S4 can send uncompressed video signals through HDMI cables to display content on compatible televisions. No need to buy separate AVR receivers anymore. Simply plug the soundbar into your TV’s AV input and start enjoying movies and music right away.
The Polk Audio Signa S4 is equipped with two built-in amplifiers, each delivering 50W per channel.
This ensures excellent sound quality even if you’re watching movies or listening to music with low volumes. And since there are no extra wires required, you won’t have to worry about tripping over cords.

The Signa 4 also offers a variety of connections including a pair of RCA outputs, one set of speaker terminals, a single line-level input, a USB port, and a front-panel headphone jack.
This model is designed to fit into smaller spaces and features a sleek black finish.
Also Read: Best Soundbar under $500
How does it sound?
The Signa S series soundbars offer superior audio performance thanks to their powerful amplification system and dual satellite speakers.
The result is a rich, clear sound that fills every corner of your home. It offers a dedicated center channel, true 3D surround sound for an immersive audio experience.
Pros:
- Easy setup
- Simple design
- Great sound quality
Cons:
- Not ideal for large rooms
Specifications
Brand | Polk Audio |
Model | Signa S4 |
Type | Soundbar |
Release Year | 2021 |
Dimensions | |
Sound Bar: | 41.2 x 3.7 x 2.4 inch (104.6 x 9.5 x 6.0 cm) |
Subwoofer: | 7.9 x 12.9 x 11.0 inch (20.0 x 32.8 x 28.0 cm) |
Drivers | |
Sound Bar | |
L/R Tweeter | (2) 1 inch / 25mm (Round) |
L/R Mid | (2) 4.7 x 1.6 inch / 120mm x 40mm (Racetrack) |
Full Range Center | (1) 1 inch / 25mm (Round) |
L/R Elevation | (2) 2.6 inch / 66mm (Round) |
Subwoofer | |
Woofer | (1) 5.9 inch / 15 cm (Round) |
Specs | |
HDMI (eARC) | 1 |
Optical Input | 1 |
3.5 mm input | 1 |
Bluetooth | ✔ |
USB-A | 1 |
In the Box | |
Sound Bar | ✔ |
Subwoofer | ✔ |
AAA Batteries | 2 |
HDMI Cable | ✔ |
Optical Cable | ✔ |
Quick Start Guide | ✔ |
Registration Card | ✔ |
Remote Control | ✔ |
Safety Card | ✔ |
Sound Bar Power Cord | ✔ |
Subwoofer Power Cord | ✔ |
Wall Mount Spacers | ✔ |
Wall Mount Template | ✔ |
Features | |
Dolby Atmos | ✔ |
Wi-Fi | ✔ |
Bluetooth | ✔ |
Wireless Subwoofer | ✔ |
Voice Adjust | ✔ |
Optimized Sound Modes | ✔ |
Height Channels | ✔ |
Discrete Center Channel | ✔ |
Sound Stage | ✔ |
Easy Setup | ✔ |
Conclusion
If you want a high-quality soundbar that will look good in any room, then the Polk Audio Signa S Series is worth checking out. It comes with everything you need to get started right out of the box.
Frequently Asked Questions
Does Signa S4 have Wireless Subwoofer?
Yes, Polk Signa S4 has Wireless Subwoofer for clutter-free music.
Where can I download the manual?
You can download the manual by clicking here.