The VIZIO SB2821-D6 vs VIZIO SB3651-E6 comparison proves that these soundbars have many common features. Based on our rating, SB2821-D6 has a total rating of 4.8 out of 10 versus 7.6 for SB3651-E6. The set of control buttons for competitors is the same and is: power, input, Bluetooth, volume down, volume up.
Both soundbars have active amplification type. A significant difference between the units in the number of channels, the VIZIO SB2821-D6 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 VIZIO SB2821-D6 got our rating of 6 out of 10, and the VIZIO SB3651-E6 7 for its audio features and specs. 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. Only the SB3651-E6 supports HDMI Audio Return Channel (ARC). Both soundbars have a USB connector. For connectivity, the SB2821-D6 received a rating of 4/10 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 VIZIO SB2821-D6 got a rating of 5, and VIZIO SB3651-E6 4 out of 10.