The world of the best soundbars has been hotting up this year, with great price crashes on some higher-end Dolby Atmos models, and a load of five-star models at the more affordable end of the scale. And even in that climate, the Polk Audio Signa S4 really hots things up.
That's because it's extremely well-equipped – featuring 7 speakers in the soundbar alone, including two dedicated upfiring Dolby Atmos drivers, plus a separate wireless subwoofer. You don't find much else with those kind of specs for £329/$349. In fact, you basically don't find anything else like it – this could really crash the high end of our best soundbars list once we've had a chance to test it.
The competition at this price tends to either focus on great stereo and dialogue without Dolby Atmos (such as the Yamaha SR-C20A), or the Dolby Atmos is created using smart virtualisation without dedicated upfiring drivers (such as in the Sonos Beam 2nd Gen or Sony HT-G700).
But real upfiring drivers will give a more immersive effect, and that's what you've got here. The two height channels are combined with three regular channels: left, right and centre. The left and right each feature a tweeter and mid-range drivers, while the centre is a single full-range driver that aims to keep dialogue clear.
The subwoofer features a 5.9-inch driver, which is not huge, but should help really add impact to the bass compared to a soundbar alone.
It'll connect over HDMI eARC so it's simple to connect to the TV, and its volume can be controlled from the TV's remote. You can use its remote to switch sound modes, including a Night Mode for limiting its loudness. There's also Bluetooth for streaming music to it.
The soundbar measures 1046x95x60mm, which means it's about as wide as a 48- or 50-inch TV – so you'll want to use it with sets between that size and 65 inches, really.
There must be a downside for this kind of spec at this price, right? Well, there's one really notable missing feature, and another one that I'm much less worried about.
The most important thing that isn't here is HDMI passthrough. Some soundbars have an HDMI input as well as an HDMI connection to your TV, which enables them to pass video through, and means you don't lose the use of that HDMI port on the TV for connecting one of the best Blu-ray players or a PS5 or whatever. This is especially useful on cheaper TVs, since they tend to have fewer HDMI ports, so each one is more precious.
It also means that if your TV doesn't support Dolby Atmos (again, which is likely to the case with more budget TVs), you can connect an Atmos-ready source directly to the soundbar and still enjoy the full Atmos effect.
Since people with more budget TVs seems to be who this soundbar is aimed at, the lack of HDMI passthrough is a real shame. But Polk Audio is far from alone here – the Sonos Beam also doesn't have HDMI passthrough – so I won't slam this machine for missing it. It's just something to be aware of.
The second thing missing feature of note is Wi-Fi – there's no streaming or smart functionality here outside of Bluetooth. But again, for the price, I see no issue with that.
This looks like a really impressive soundbar, and Polk's reputation is all about producing great-sounding speakers that seem like they should cost more than they do, so this fits right in. It's due for release today, December 15th 2021.