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VIZIO SB4021M-A1 Home Theater Sound Bar Review

Al Landes Profile image

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Updated July 5, 2022

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VIZIO is known for its TVs, but you wouldn’t say the same when it comes to stand-alone sound systems. When the UPS guy delivered the rectangular box to my door, I couldn’t figure out how VIZIO got a TV into the box. As it turns out, VIZIO didn’t, because what was inside was their SB4021M-A1 Home Theater Sound Bar. If you like shorter sound bars, it’s easy to rate as the best soundbar if you do not want to try lots of other sound bar systems.

The VIZIO SB4021M-A1 Home Theater Sound Bar consists of a soundbar and a stand-alone wireless subwoofer. The 5-pound soundbar is 40-inches long and has a euro-curved shape that compliments the glossy piano black nicely.  A pair of removable stands at the bottom prop it up firmly, providing you’re using it on a tabletop. VIZIO supplies two wall mounting brackets and a template for mounting the soundbar on a wall, but you’ll need to supply the appropriate type of screws (the stands must be first unscrewed from the bottom of the soundbar). As always, take note of any electrical wiring inside the wall, as well as any regulations about what is allowable in the case of an apartment dweller or condo owner. For a great budget sound bar, click the Yamaha YAS 101 soundbar review.

VIZIO SB4021M A1 Home Theater Sound Bar length of bar

Now obviously the soundbar has a power supply as does the 20-pound wireless subwoofer, which can be placed anywhere in the room since the bass is omnidirectional. The sub’s 2.4 GHz wireless system easily pairs to the soundbar, which is to say they connect with a press of a button on each. VIZIO says you can move the subwoofer up to 60 feet away, but, I found that the signal red-lined at 50 feet. Exceeding that and you’ll begin to witness signal interference. The sub, like the soundbar, is also a glossy piano black and differs from the conventional as the grills are on the side — it isn’t bottom or front-firing, but side. For a wider sound bar, read our Vizio S5451W C2 54-inch 5.1 home theater sound bar review.

VIZIO SB4021M A1 Home Theater Sound Bar sound bar inputs on back

All of the controls can be accessed through the short remote, which has a slightly curved design that makes it easy to hold. The buttons require a firm press, but are spaced sensibly with a direction pad taking up the middle, the power at the very top, and inputs, mute, and menu horizontally arranged at the bottom. There’s no backlighting, but as there are so few buttons to deal with, this shouldn’t be much of a concern. The menu button provides access to two specialized features, besides the expected volume and treble and bass levels (pressing up/down on the direction pad affects volume as a matter of course). These consist of SR TruVolume (to keep the volume the same regardless of what’s playing) and SRS TruSurround HD (simulated surround). There’s also controls placed on the top of the soundbar. A display on the soundbar’s front illuminates with text when a button is pressed.

VIZIO SB4021M A1 Home Theater Sound Bar subwoofer back ports

My testing begins with the “American Greed” TV show, which heavily favors a narrator. The midrange from the sound bar’s speakers is very precise — there wasn’t any “bleeding” to muddle my understanding of the dialogue, even with the volume increasing nearly to the maximum. Add to that the bass effect coming from the sub (although subtle here) which kept the narrator’s deep voice from sounding thready. Ultimately, the SB4021M-A1 soundbar is suitable for day-to-day watching.

The digital amplification driving the speakers is efficient, and the speaker-set themselves is more authoritative than might be expected from the moderate price. The wattage isn’t provided, but it seems fair to say that it falls well shy of 100 watts. On the plus side, even when the volume was raised to the max, there wasn’t any hiss or distortion being brought on.

VIZIO SB4021M A1 Home Theater Sound Bar menu display

Switching to a Blu-ray disc of The Avengers brings out a much greater level of bass from the subwoofer, and the pair of speakers in the sound bar isn’t being overridden and still commands attention. This isn’t just partly due to there being 2 drivers to each “channel” (left/right) radiating out from the soundbar, but also partly due to tight control over the speakers’ harmonic distortion which doesn’t inhibit the intensity of the audio.

Switching on the simulated surround and repeating the same scenes I had just watched provides me with two details: the first being the volume seems to increase overall with the “surround” on — this might just be perception, but something I witnessed.  Secondly, the effect seems to work best if you have equidistant walls for the pseudo-effect sound waves to bounce off of. Third, you don’t get too close. This won’t be an issue with larger displays since you’ll be seated far enough away to harness the display’s true quality, and in turn, the “surround” effect can do its thing.

VIZIO SB4021M A1 Home Theater Sound Bar remote

The USB socket at the front side enables MP3 stored content to be played directly through the soundbar using the direction pad on the remote. Frankly, I think being able to stream to the soundbar using Bluetooth, as you can on the Sony HTST7 HD Sound Bar, would be more useful. But, perhaps the decision not to include it comes from wanting to keep the price down. At any rate, this works only with USB drives such as the 8 GB thumb drive, filled with some high-resolution tunes (Fleetwood Mac for example), that I’ve inserted into it. The audio sounded significantly better than mid-priced audio docks and some computer speakers I’ve listened to in the past. For example, Jesse’s Girl (Rick Springfield) not only gained a solid and substantial bass from the soundbar, but at no time did the vocals seem thready or the electric guitars subdued. Of course, the subwoofer wasn’t hurting this either. The best bass response from the soundbar seems to occur with the volume raised a bit over the midpoint.

Editor’s Rating:



Bottom line: At $229 retail, the VIZIO SB4021M-A1 Home Theater Sound Bar provides the means for significantly improving the audio output from your TV. The VIZIO can perform up to this task, providing that the size of the viewing space is not so large as to overwhelm its audio capabilities (performing better in a bedroom location than that of a living room). With this in mind, most will find the SB4021M-A1 a competent choice for home theater use. Although, for a pair of speakers to use at your desk, you’ll want to check out our Edifier Luna E review.


  • Auto pairing of sound bar and subwoofer
  • Durable and well-styled sound bar cabinet


  • No separate subwoofer volume control
Al Landes Profile image