The Polk Signa S4 is an entry-level 3.1.2 Dolby Atmos soundbar with a wireless subwoofer and Polk's VoiceAdjust dialog-boost processing. Its single HDMI port supports eARC — handing off uncompressed Atmos from a modern TV over one cable — while optical TOSLINK and a 3.5mm analog input cover older sources. The rear USB-A port is for firmware updates only, not media playback, and optical and analog inputs cannot carry Dolby Atmos (eARC required for Atmos). Power is a detachable 2-prong figure-8 cord, so a universal IEC C7 replacement fits if you lose the original.
3.1.2 Dolby Atmos soundbar with wireless subwoofer, HDMI eARC, optical, 3.5mm aux, and firmware USB port.
Device Information
- Manufacturer
- Polk Audio
- Release Year
- 2023
- Model Number
- Signa S4
- Category
- Audio Equipment
Available Ports
| Connector | Quantity | Label | Notes |
|---|---|---|---|
| HDMI 2.0b (Type A – Standard) | 1 | HDMI (eARC) | eARC return from TV for uncompressed Dolby Atmos. No HDMI pass-through input on this bar. |
| Optical TOSLINK (S/PDIF) | 1 | Optical IN | Digital optical input. Stereo PCM / Dolby Digital only — no Atmos. |
| 3.5mm TRS (Stereo Audio) | 1 | AUX IN (3.5mm) | Analog stereo line-level input. |
| USB Type-A (USB 2.0) | 1 | USB (service) | Firmware updates only. Does not play audio from USB storage. |
| IEC C8 (Figure-8 Inlet) | 1 | AC Power (C8 figure-8 inlet) | 2-prong figure-8 detachable cord (Polk AM6214-A-compatible). |
Notes & Compatibility
The HDMI port is labelled eARC but is typically HDMI 2.0-class on this budget tier (audio-only return to the bar — the Signa S4 has no HDMI pass-through input). Atmos only works via eARC; the optical and 3.5mm analog inputs are stereo-only. Power cord is a 2-prong figure-8 type compatible with the Polk Signa S1/S2/S3/S4 AM6214-A replacement cord.
