Comparison of Vizio M21d-H8 and VIZIO SB3651-F6 will reveal the best features offered by the devices. SB3651-F6 is a better soundbar than the M21d-H8. Its sound profile is well-balanced and stereo performance is better. According to the results of our comparison, M21d-H8 received 5 points out of 10 possible, and SB3651-F6 was rated 6.8 points.
The M21d-H8 is rated 5 of 10 against 8 for the SB3651-F6 according to the audio features rating.
It worth understanding the difference between the two types of amplification: a passive soundbar does not have its own amplifier and receives amplification from the signal source, while an active soundbar has a built-in amplifier. The same active type of amplification is used in the M21d-H8 and the SB3651-F6.
There are stereo soundbars and multichannel ones. It is with the help of multichannel devices that you can get volumetric sound. It is worth noting one of the main differences, the M21d-H8 has 2.1 channels, while the SB3651-F6 has 5.1 channels.
|Output power, W||N/A||N/A|
|Separate speaker (in package)||0||2|
|Separate speaker connections||has not||wireless|
Soundbars can have a built-in or external subwoofer. The first type is inseparable from the soundbar body, but for the second, you can choose a good location for deep bass. A built-in subwoofer is only present in the M21d-H8. The SB3651-F6 comes with an external subwoofer.
|Separate subwoofer (in package)||✖||✔|
|Separate subwoofer connections||✖||wired, wireless|
Unlike stereo, when reproducing multichannel sound, each specific direction of sound corresponds to its dedicated channel with a separate independent loudspeaker, which creates a three-dimensional sound stage. The M21d-H8 received rating 5 out of 10 for multichannel audio processing, but the SB3651-F6, in the same category, earned 6 out of 10 points.
The peculiarity of Dolby Atmos is that this format is object-oriented, that is, each object of the audio signal is sounded separately and linked to its spatial location. If we look at the models in terms of Dolby Atmos support, then none of these soundbars can work with this technology.
DTS:X is an algorithm for processing sound scenes by the processor, linking directly to objects, rather than channels, and calculating the optimal distribution of sound output in a room. This ability to reproduce surround sound with DTS:X technology is not implemented in any of the soundbars in this comparison.
|Dolby (other)||Dolby Digital||Dolby Digital|
|DTS (other)||DTS Virtual:X||DTS Virtual:X|
The possibility to listen online to millions of songs from one device has become a reality thanks to streaming services.
None of the two models is not implemented AirPlay function. The popular Spotify service is available on the SB3651-F6.
|Apple Music (AirPlay)||✖||✖|
|Other streaming services||has not||Pandora, Chromecast, iHeart|
The existence of a sufficient number of current connectors significantly expands the functionality of the device. For example, only through HDMI is it possible to implement the transfer of object-oriented formats, and the presence of a Bluetooth connection will allow remote control, etc. The devices received different ratings for connectivity: Vizio M21d-H8 was rated 6 out of 10, and VIZIO SB3651-F6 was rated 8 out of 10.
The presence of Wi-Fi in the soundbar allows you to get rid of wires when connected to a sound source and get minimal audio latency when playing content from streaming services. Wireless connection via Wi-Fi is possible on the SB3651-F6.
Bluetooth connection is now one of the main communication protocols for speaker systems, which provides excellent quality and minimal audio latency. The availability of Bluetooth protocol, we can see in both models. The M21d-H8 has 1/1 HDMI inputs/outputs, but the SB3651-F6 got 1/0 HDMI inputs/outputs from the manufacturer.
HDMI ARC is a very usefull technology that creates a two-way communication channel between a TV and another device. This is convenient since there is no need to use optical and other cables in the system. HDMI ARC is basic for both soundbars. Connecting external devices via USB can be done on both models.
|Optical digital input/output||1/0||1/0|
|USB||1 (USB 2.0)||1 (USB 2.0)|
|Coaxial digital input/output||0/0||1/0|
|Analog audio input/output (RCA)||1/0||1/0|
Voice control is designed to make operating the device more convenient. This allows you to control basic soundbar functions from anywhere in the room.
Proprietary applications allow you to control your soundbars remotely. This is possible both via Bluetooth and Wi-Fi. The SB3651-F6 has its own remote control application. Only Vizio M21d-H8 has a built-in microphone.
Some soundbars can be part of a multi-room system and it is an affordable solution for sounding the whole house. However, it is impossible to create a multiroom system based on each of these soundbars.
|Voice control||Amazon Alexa, Google Assistant, Siri||✖|
|Size (Wx H x D), cm/in||98 x 11.4 x 18.8/39 x 5 x 7||91.4 x 5.3 x 8.1/36 x 2.1 x 3.2|