
Polk Audio Signa S4
Score: 84/100
Bose Smart Ultra
Score: 82/100Rankings

The Polk Signa S4 is a slim 3.1.2-channel soundbar with Dolby Atmos and a powerful wireless subwoofer, delivering strong bass and clear dialogue. Its lack of a standard HDMI input and occasional Bluetooth hiccups limit connectivity flexibility. Ideal for budget-conscious TV owners seeking immersive sound in small to medium rooms.

The Bose Smart Ultra Soundbar offers premium nine-speaker Dolby Atmos performance with ADAPTiQ calibration and dual-assistant voice control. Its lack of an integrated subwoofer and bright tuning may limit bass impact, making it ideal for users seeking high-end features in a single bar.
| Attribute | ![]() | ![]() |
|---|---|---|
— | 5best | |
410 Wbest | — | |
15 cmbest | — | |
| ↓ lower better | 4 kgbest | 5.75 kg |
3 yearsbest | 1 years | |
104.6 cmbest | 104.5 cm | |
6.1 cmbest | 5.82 cm | |
9.4 cm | 10.69 cmbest |
Click an attribute name to sort · Green = best, red = worst (relative to this comparison)
| Attribute | ![]() | ![]() |
|---|---|---|
Audio(2) | ||
Audio Channels | 3.1.2 | 5 |
Wireless Subwoofer | true | false |
General(1) | ||
Warranty Period (years) | 3 years | 1 years |
Design(4) | ||
Soundbar Weight (kg) | 4.0 kg | 5.75 kg |
Soundbar Width (cm) | 104.6 cm | 104.5 cm |
Soundbar Height (cm) | 6.1 cm | 5.82 cm |
Soundbar Depth (cm) | 9.4 cm | 10.69 cm |


Products in the top-left offer the best value (high score, low price).

Professional reviewers commend the Signa S4 for its impressive bass output, clear dialogue thanks to VoiceAdjust, and effective Atmos height effects, noting it offers strong value in the entry-level Atmos segment. However, they criticize the missing standard HDMI input and the need for careful bass balancing.
Everyday users love the easy wireless sub setup, the room-shaking bass, and the clear speech reproduction, especially for movies and sports. Common complaints revolve around the sub's heft, occasional Bluetooth hiccups, and the inability to connect multiple HDMI sources, with some noting the bass can dominate mids if not tuned.

Professional reviewers praise the Bose Smart Ultra for its AI Dialogue clarity, TrueSpace upmixing, and ADAPTiQ room calibration, noting its accurate and spacious sound. However, they criticize the bright default tuning, limited height immersion without satellites, and the absence of a bundled subwoofer, which reduces bass impact compared to larger systems.
Everyday users love the ultra-crisp vocals, immersive surround feel, and the convenience of voice control, while consistently noting that the sound can become treble-heavy and that bass lacks punch without an optional subwoofer. Sync issues with non-eARC TVs are also a recurring complaint.
“huge soundstage”

“powerful bass that rumbles behind couch”


