The Polk Audio SIGNA S2 vs VIZIO SB3651-E6 comparison proves that these soundbars have many common features. Based on our rating, SIGNA S2 has a total rating of 5 out of 10 versus 7.6 for SB3651-E6. The competitors' control buttons are different: power, volume down, volume up, source, Bluetooth and power, input, Bluetooth, volume down, volume up, respectively.
Both soundbars have active amplification type. A significant difference between the units in the number of channels, the Polk Audio SIGNA S2 has 2.1 versus 5.1 for the VIZIO SB3651-E6. Competitors do not have a built-in subwoofer. Rivals have wireless connection to separate subwoofer. The Polk Audio SIGNA S2 got our rating of 6 out of 10, and the VIZIO SB3651-E6 7 for its audio features and specs.
Each of rivals supports AirPlay. Spotify support is available on the SB3651-E6.
Only the VIZIO SB3651-E6 can connect to the Internet via WI-FI. Rivals from our review have Bluetooth support. Each soundbar has 1/0 HDMI inputs/outputs. The HDMI Audio Return Channel (ARC) feature supports both devices. For connectivity, the SIGNA S2 received a rating of 6/10 versus 8/10, respectively. App control is available for the SB3651-E6. A built-in microphone is present only on the SB3651-E6. Soundbars do not have Multi-room support.
None of soundbars equipped with Dolby Atmos multichannel audio decoder. The soundbars do not support the surround sound technology DTS:X. For multichannel surround, each of the opponents received 4 points out of 10.