Skip to main content

Digital Trends may earn a commission when you buy through links on our site. Why trust us?

Vizio M-Series 5.1 soundbar review (M51a-H6): The bar to beat

Vizio M-Series 5.1 soundbar (M51a-H6)
MSRP $299.99
“The Vizio M-Series 5.1 is a knockout value.”
  • eARC, Dolby Atmos, DTS:X support
  • Impressive subwoofer
  • Seamless surround effects
  • Comprehensive control
  • Excellent fidelity
  • One HDMI input
  • Less suitable for larger rooms

Having recently reviewed the Vizio Elevate soundbar, which produced outstanding Dolby Atmos surround sound (for a steep price), I’ve been eager to take a look at Vizio’s lower-priced M-Series 5.1 (M51a-H6) soundbar as well. With virtual Dolby Atmos and DTS:X onboard and a compact profile, the $300 soundbar system has all the makings of an incredible value. But even going in knowing all this, I came away surprised. Let’s take a look.

Out of the box

At first glance, the M-Series 5.1 may look a bit … boring. But that’s sort of the point. The soundbar doesn’t call attention to itself, and I consider that a good thing — you should be able to hear the gear without it being a visual intrusion. Vizio did a fine job of creating an attractive system that disappears into your room. It’s compact, can slide right under most Vizio TVs, and comes in a smooth, charcoal-gray finish.

The system comes with a 36-inch-wide soundbar that packs six drivers — three mid-woofers and three tweeters in a left, center, right configuration — as well as two surround speakers with a single midrange driver for each, and a subwoofer with a robust six-inch driver at the bottom.

The backside of the soundbar is pretty straightforward. There is a power port and an auxiliary input port that can be used for a smart speaker if you’d like the smart speaker to control the system or be heard through the surround sound system. There are also two HDMI connections, one for connecting a single device and another that supports eARC for lossless Dolby Atmos and DTS:X surround signals — that’s a pretty impressive inclusion at this price point.

Everything you need comes in an incredibly well-organized box

Dan Baker/Digital Trends

The back of the surround speakers have a single RCA port that connects the speakers to the subwoofer, as well as a screw hole that can be used to mount the speakers using included mounting brackets.

If you’re familiar with Vizio soundbars, then you know that everything you need comes in an incredibly well-organized box. There are two power cords (one short and one long, in case your subwoofer is further away from an outlet), two extremely long surround sound speaker cables, an HDMI cable, a remote, batteries, an optical cable, a couple of analog cables, and the aforementioned hardware to mount the speakers.

Setup options

There are two different setup scenarios for the M-Series 5.1. One is the more conventional setup where the soundbar is positioned upfront, the surround speakers behind you, and the subwoofer back with the surround speakers (which gets the surround signal wirelessly and powers the surround speakers).

Setup is plug-and-play and totally automated.

The other setup option (which works well for people who may not have as much room) is to have the surround speakers flank the soundbar at the front, with the subwoofer also toward the front of the room. Vizio claims that even with this setup, the M-Series 5.1 can still pull off some pretty impressive surround sound effects.

Dan Baker/Digital Trends

Setup is plug-and-play and totally automated. After plugging the soundbar and subwoofer into power outlets and turning the system on, the two components will automatically connect to each other and you’re good to go. If you happen to be using the M-Series 5.1 in a massive, cavernous room, there could be some issues with the subwoofer being too far away from the soundbar and losing some of its signal, which manifests itself through a little popping noise. But considering this system isn’t intended for larger rooms, I don’t see this being an issue for most folks

Much like the Vizio Elevate, the M-Series 5.1 system has a comprehensive suite of controls, all of which are managed via the included remote control. With the remote, you can manage independent surround speaker balance, overall surround speaker level, subwoofer level, bass and treble levels, and a fair amount of preset EQ options. This kind of control is essential for dialing in the system’s sound to work well with various speaker/subwoofer placement scenarios and room characteristics. With a little bit of tweaking, I was able to get the system right where I wanted it.

Dan Baker/Digital Trends

Sound quality

But how does it sound? In short, the Vizio M-Series 5.1 sounds great. In fact, at this price range, it has no business sounding as good as it does — even for Vizio, which is known for putting out some fairly high-value soundbars.

The M-Series 5.1 created a convincing circle of sound.

The system doesn’t pull off Dolby Atmos effects quite as well as a system with upfiring speakers (like the Vizio Elevate), but the fidelity is impressive and the surround effects are seamless and contiguous.

The surround effects in the intro of Mad Max: Fury Road (one of my go-to Atmos surround test tracks) swirl around you, and if there are any holes in the presentation, you’ll notice right away. The M-Series 5.1 created a convincing circle of sound, with the blend between the surround speakers and the soundbar sounding excellent.

The virtual Dolby Atmos effects certainly did increase the perceived height of the overall presentation and improved the depth as well. I just didn’t get the sensation that objects were right above me like I did with the Vizio Elevate. When the first chase scene ensues in Fury Road a dune buggy flies overhead, and on proper Dolby Atmos systems, it sounds as if the vehicle races up from behind and flies right over you. With the M-Series 5.1 soundbar, the dune buggy seemed to come through me as opposed to above me.

I find that this track is also a good stress test because the low, gravelly voice of the narrator will push the limits of most soundbars, which often lean heavily on the subwoofer for midbass frequencies. I’ve frequently found that it seems as if most of the voice is coming from the subwoofer, but in my testing, I found no undue attention called to the subwoofer. It seemed as if the voice was anchored to the soundbar, with the bass simply omnipresent — truly impressive.

If you want your living room to feel more like a theater, the M-Series 5.1 absolutely pulls that off. Unlike other soundbars I’ve tested, the treble here is not too sharp, the dialog is never muffled, and the midrange is clear and well-defined. And while soundbars aren’t known for being all that “musical,” I did run a few music tracks through the M-Series 5.1 and it produced the same crisp fidelity as it did for movies. There wasn’t a great deal of instrumental separation, and the sound stage isn’t especially deep — after all, the M-Series 5.1 is not an audiophile product meant to compete with a dedicated music system — but the bass is rich, the instrumental textures are very good, and the system provided a pleasant, room-filling experience.

Our take

People go into budget-friendly soundbars with managed expectations. For most, as long as it sounds better than the TV’s built-in speakers, it’s usually fine. But the Vizio M-Series 5.1 defies those expectations and, as such, I think listeners will be blown away at first listen. For the price, the Vizio M-Series 5.1 is a knockout.

Is there a better alternative

No. Vizio also offers its SB36512-F6 soundbar, which has two upfiring Atmos channels, for the same price. However, I don’t like its design as much, and I think the fidelity of the M-Series 5.1 is a bit better. Also, the M-Series 5.1 supports eARC for higher-quality audio while the SB366512-F6 offers standard ARC.

How long will it last

The Vizio M-Series 5.1 seems well-built and should last as long as it takes for you to get the itch to upgrade.


Vizio offers a one-year warranty on its soundbars when purchased from an authorized retailer. More warranty information can be found here.

Should you buy it?

Yes. The M-Series 5.1 soundbar is a tremendous value and offers an extremely fun cinematic sound experience.

Editors' Recommendations

The best soundbars 2023: which should you buy?
Sonos Arc Dolby Atmos Soundbar in white with Sub

While the audio quality from the newest and best TVs is getting better, it's still a foregone conclusion that any TV you buy is going to need a better sound setup. This can come in many forms, such as complex Dolby Atmos surround sound systems complete with an AV receiver, many speakers, a subwoofer and more. But for most people, that just isn't doable, either for budgetary reasons, space limitations, or just for the pain frustration factor — and that's where the best soundbars come in.

Luckily, there's a wide variety of soundbars. Some can deliver room-filling immersive sound with Dolby Atmos support while others come with subwoofers and additional surround speakers you can mount on a wall or on stands; some are even wireless. Some have big booming volume while others are more suited to smaller rooms like apartments, and some are just designed to blow you away completely. There's something for every situation and budget.

Read more
Best headphones for 2023: Sony, Sennheiser, Apple, and more
Sony WH-1000XM5 wireless headphones hanging on wall hook in front of a mirror.

What are your priorities when it comes to finding the best headphones for you? Is it lush, rich sound over noise-canceling technology? Or do you favor comfort and style above all? Ah, maybe it's all about price, which is totally fair, too. A great pair of headphones — and by headphones, we typically mean the over-ear variety. If you're looking for earbuds, we have a roundup of the best of those, too — should do what you need them to do for however you plan to use them, from working out to commuting to flying to shutting out your screaming kids for a few minutes of bliss.

We've tested hundreds of pairs of headphones, and as far as we're concerned, the Sony WH-1000XM5 are the best headphones for most people. With a comfortable design and slick appearance, plus continued improvements in noise-canceling, call quality, sound quality, and charging speed, Sony leaves almost no box unchecked when it comes to headphone perfection.

Read more
The best smart speakers for 2023
Amazon Echo Dot (4th Gen) with Clock front

Smart speakers are an integral part of any smart home, often serving as the brains of the entire operation. Beyond pumping out impressive audio or giving you updates on the morning news, smart speakers can listen to voice commands before passing out instructions to the rest of your gadgets. Functionality varies widely by product, making it important to find the best smart speaker for your setup.

Thankfully, it’s hard to pick a dud in today’s loaded marketplace. Whether you’re an Apple loyalist, a Google enthusiast, or an avid user of Amazon Alexa, just about every big tech company is churning out incredible smart speakers. But if you need some help narrowing down all your options, here’s a look at the best smart speakers of 2023.

Read more