Soundbars aren't just for watching TV and movies. They can do music too, and models like the Polk Signa S3 prove that musical sound from a bar doesn't have to cost a fortune. The Signa's superlative audio performance is anchored by a potent subwoofer that helps bolster the bottom end of both tricky soundtracks and bass-heavy music.
The Polk adds must-have features too, including Wi-Fi and Chromecast streaming that go missing from cheaper models like the Vizio V21. The Signa lacks the DTS Virtual:X processing of rivals Vizio and Yamaha, however. Virtual:X helps create a convincing surround field without the use of rear speakers, and it pushes those brands ahead for TV watching.
The Vizio V21 is a better choice for users who want a soundbar that does music and movies in equal measure; the Polk is better for music lovers who crave exciting, detailed sound and punchy bass.
The Polk Signa S3 is a soundbar/wireless subwoofer combo that builds on the success of other Polk models like the Signa S1 and the Command Bar. On the surface it looks similar to 2014's Signa S1 -- only with a nicer, wool-like grill -- but the internals have received a number of important upgrades.
The Signa S3 includes Chromecast built in, which enables users to stream music over compatible apps like Amazon Music HD, Spotify and Tidal. It lacks a built-in voice assistant, but you can control music using a separate Google Assistant speaker like the Nest Mini.
Sound processing includes Polk's Voice Adjust technology, which enables users to adjust the level of the dialogue, as well as Movie, Music and Night modes. The S3 lacks Dolby Atmos decoding found on more-expensive soundbars, but it does have Dolby Digital 5.1 via a single HDMI ARC connection. The soundbar also includes a digital optical input and a 3.5mm auxiliary.
The main speaker is compact at 35-inches wide and less than 2 inches in height so it shouldn't block your TV's IR port. The bar itself comprises four drivers -- two woofers and two tweeters -- and the unit can be wall-mounted without the use of a separate bracket. The ported, wireless subwoofer is relatively large for a budget unit, and it's made of wood (MDF), rather than plastic like some competitors.
The S3 is more user-friendly than the Vizio V21, and the remote has clear markings for each of the functions as well as the inputs. No cycling through inputs or sound modes here -- just press the one you want.
I tested the Polk Signa S3 against two other 2020 soundbars -- the Vizio V21 and the JBL Bar 2.1 Deep Bass -- and it pulled ahead of the other two in one important respect: it was the most fun with music. When judged on its own the Vizio sounds great, but in direct comparisons to the Polk it came across a little chesty and boxed-in. The Polk burrowed further into recordings, releasing key details, making it easier to forget I was listening to a soundbar.
Whether I was watching a show streaming from Netflix or listening to some Spotify, the Polk Signa S3 was natural sounding with a decent stereo soundstage, plus a forcefulness and feeling of power when needed. There was no sense that it was holding back or distorting, and it delivered impressive scale for a relatively compact speaker.
I started with Mitski's heartbreaking Your Best American Girl, and on the Polk her performance sounded both forceful and brutal -- but the speaker was also able to surface tiny details such as the little "hmph" at the start of the song. The S3's tuning tends toward the exciting end of the spectrum, however, so the distorted middle eight was hardest to listen to among the three 'bars. In comparison, the Vizio in particular sounded a little veiled and lacked the Polk's dynamics.
The Polk also belted out big productions like Kamasi Washington's version of the Fists of Fury theme. The Vizio sounded laid back but heavily separated. Turning off Virtual:X on the Vizio reduced the carnival midway effect a little, but I still wanted to go back and listen to the song on the Polk.
While Virtual:X can be a distraction during music, it helps the Vizio with many movie soundtracks. During the Thanator chase scene from Avatar (at 26:53), the Polk managed to convey the dialogue but the swirling insects and stomping creatures were a little blunted by comparison. Adjusting the Polk's bass control and sound mode didn't help bring back the slam of the Vizio or the JBL.
In the lobby scene from The Matrix, however, the tables were turned. The Vizio struggled with the pulsing bass score, but the Polk's larger, more muscular sub was better able to convey each of the notes.
The Polk Signa S3 is a strong soundbar value especially if you can get it for less than its $250 list price. It offers a superior performance with music, a more powerful sub and a host of new tech including HDMI ARC and Wi-Fi streaming. When it comes to movies, it's not as punchy as the JBL Bar 2.1 or as evocative as the Vizio V21, however, so either of these may be better choices if you're not going to listen to much music on your soundbar.