l would like to share my experience after comparing and testing two soundbars – VIZIO SB2821-D6 vs Vizio M21d-H8. The VIZIO SB2821-D6 was rated 4.8, while the Vizio M21d-H8 has a rating 5. The soundbars are equipped with a different number of buttons, power, input, Bluetooth, volume down, volume up for the SB2821-D6 and power, volume down, volume up, source, Bluetooth for the M21d-H8.
Each of the models under consideration has active amplification type. By the number of channels, the devices do not differ. A built-in subwoofer is available only in the Vizio M21d-H8. Rate 6 out of 10 received the VIZIO SB2821-D6 for audio features and specs, but the Vizio M21d-H8 received 5 out of 10.
Soundbars do not have AirPlay support. The units in this comparison do not support Spotify.
Both models do not have a wireless Wi-Fi interface. Soundbars from this comparison have Bluetooth support. The HDMI Audio Return Channel (ARC) is implemented only in the M21d-H8. Connecting devices via USB is possible in both models. We rated the connectivity of the SB2821-D6 at 4 out of 10, while the M21d-H8 was rated 6/10. None of these soundbars can be controlled using the app. The Vizio M21d-H8 equipped with a microphone. The models under consideration cannot become part of a multiroom system.
Dolby Atmos audio decoder support is not implemented in either the SB2821-D6 or M21d-H8. Devices from this comparison cannot process surround sound due to lack of DTS:X. The same score of 5/10 was put to the soundbars for multichannel surround support.