The Vizio M Series M512a-H6 is a 5.1.2 setup released in 2021. It's a mid-range offering from the manufacturer that's one of the few bars in its price range to include rear satellites for a more immersive surround sound. As with many Vizio bars, you have to wire the satellites to the sub, which isn't ideal for every living room setup. Without up-firing drivers on its satellites, it doesn't sound quite as immersive as the more premium Vizio Elevate. However, the two up-firing drivers in the bar make a real difference with Dolby Atmos content, especially compared to budget selections like the Vizio M Series M51a-H6.
Note: We bought and tested another unit in compliance with our out-of-spec policy. We've tested the new unit and have updated the review accordingly.
Our Verdict
The Vizio M512a-H6 is very good for mixed usage. It's a versatile 5.1.2 bar that stands out from other bars at its wallet-friendly price point. Plug it into your TV, and voices and lead instruments are clear right out of the box, thanks to its balanced sound. The sub brings rumble in the bass to bring bass-heavy genres and action-packed scenes to life, and its satellites add to the immersive feeling with movies. Compared to more premium offerings, it doesn't bring the same cinematic feeling, especially with Atmos content, but if you're on a tighter budget, it's a solid pick.
-
Bass and treble adjustments.
-
Gets loud.
-
Clear vocal reproduction.
-
Good surrounds performance.
-
No graphic EQ.
The Vizio M512a-H6 is great for vocal-centric TV shows and podcasts. It's a 5.1.2 setup, so there's a discrete center channel to improve vocal reproduction. With its balanced mids, dialogue is clear and detailed, and you don't have trouble following the action on screen. If you want voices to sound even more clear and crisp, there's a dialogue enhancement feature on hand. You can easily stream podcasts from your mobile devices over Bluetooth, though unfortunately, you can't do so over Wi-Fi, AirPlay, or Chromecast.
-
Clear vocal reproduction.
-
Dialogue enhancement feature.
-
Bluetooth-enabled.
-
No graphic EQ.
The Vizio M512a-H6 is very good for music. Its sound profile is fairly balanced out of the box, especially in the mids, where most voices and lead instruments reproduce. Thanks to its dedicated subwoofer, you get plenty of rumble in the bass. As a result, it's suitable for most music genres. A few customization tools are on hand to switch up its sound, including bass and treble adjustments. Unfortunately, you don't get a full graphic EQ to customize across the range.
-
Bass and treble adjustments.
-
Gets loud.
-
No graphic EQ.
The Vizio M512a-H6 is good for movies. Especially compared to other bars at its price point, it performs well. You can watch common surround sound formats like Dolby Digital as well as object-based formats like Dolby Atmos, which are found on most streaming services. Its satellites offer a fairly immersive listening experience, too, so sound effects seem to come from all around you as if you're right in the middle of your favorite movie. However, it doesn't reproduce the same feeling of height as more premium setups, which reduces its overall cinematic feel.
-
Gets loud.
-
Good surrounds performance.
-
No graphic EQ.
- 7.8 Mixed Usage
- 8.0 Dialogue/TV Shows
- 7.8 Music
- 7.7 Movies
- Updated Jan 29, 2024: Per TBU 1.3 methodology, we updated the text in the Stereo Sound boxes after retesting with the manufacturer's recommended settings. Also added text to Audio Latency: ARC, Audio Latency: HDMI In, and Audio Latency: Optical boxes. Some updates to the usages to be in line with these changes.
- Updated Jan 29, 2024: We've converted this review to Test Bench Update 1.3. If applicable, we've retested stereo sound based on the manufacturer's recommendations. Additionally, we've expanded our audio latency tests to the following boxes: Audio Latency: ARC, Audio Latency: HDMI In, and Audio Latency: Optical. You can see the full changelog here.
- Updated Sep 21, 2023: Added more information about the bar's PCM performance in the Audio Format Support: ARC/eARC box.
- Updated Jun 02, 2023: Converted to Test Bench 1.2. Updated the results for audio format support via ARC/eARC, HDMI In, and Optical. Added Video Passthrough to TV results as well.
- Updated Mar 01, 2023: Added cable lengths to In The Box.
- Updated Mar 01, 2023: Converted to Test Bench 1.1. With this update, we've added a Mounting test and added information aboutSubwoofer Output, Spotify Connect, and Microphone Mute.
- Updated Jan 25, 2023: We've retested the bar's sound with firmware version 2.1.0.4. Subjectively, no change in the sound with real-life content.
- Updated Sep 27, 2022: Added market comparison for the Vizio M Series Elevate M512E-K6 to the 'Height (Atmos)' box.
- Updated Aug 19, 2022: Updated review for accuracy and clarity.
- Updated Aug 07, 2022: Added information in the Sound Enhancement Features box to compare the bar's features with the Samsung HW-Q800B.
- Updated Mar 31, 2022: Based on user feedback, we have confirmed that updating the bar to latest firmware 1.3.0.7 improves the bar's latency. All relevant text has been updated throughout the review.
- Updated Feb 16, 2022: Added more info about EQ presets.
- Updated Sep 17, 2021: Updated sound and latency test results and texts after testing a new unit.
- Updated Aug 04, 2021: Review published.
- Updated Jul 30, 2021: Early access published.
- Updated Jun 14, 2021: Our testers have started testing this product.
- Updated Jun 10, 2021: The product has arrived in our lab, and our testers will start evaluating it soon.
- Updated Jun 03, 2021: We've purchased the product and are waiting for it to arrive in our lab.
Differences Between Sizes And Variants
The Vizio M512a-H6 comes in Black, and you can see the label for the model we tested here.
If you come across another version of this soundbar, let us know in the discussions, and we'll update our review.
Compared To Other Soundbars
The Vizio M512a-H6 is a mid-range 5.1.2 soundbar with satellites and a subwoofer included. It's pretty versatile, especially compared to other bars at its price point like the LG SP8YA. You won't find as many customization tools as with more premium bars, and there's not as much of a cinematic feel with Atmos content. Still, if you don't have to spend a lot on a bar, it's a great value pick.
See our recommendations for the best 5.1 soundbars, the best Vizio soundbars, and the best Dolby Atmos soundbars.
The Vizio M Series M512a-H6 is slightly better than the Vizio M Series M51ax-J6. The M512a-H6 is better for music. It has a better soundstage, and it's also better built. It even comes with two up-firing speakers. While the M51ax-J6 can get slightly louder, the M512a-H6 has slightly less compression present at max volume, resulting in cleaner audio at louder volume levels.
The Vizio M Series M512a-H6 is a more affordable alternative to the Vizio M Series Elevate M512E-K6, and it may be a better value for some users. The main difference between these two bars is that the better-built Elevate has a unique design, and its sides rotate when you listen to Atmos content for a more immersive sound. However, the M512a-H6 has a better soundstage out of the box, and its low bass is more extended. If you don't need this extra Atmos feature, it's a good value overall.
The Vizio M Series M512a-H6 is better than the Vizio M Series M51a-H6. The M512a-H6 is better built and has a better soundstage performance. It also comes with two up-firing speakers.
Depending on your listening habits, you may prefer either the Vizio Elevate or the Vizio M Series M512a-H6. The Elevate is better built and has a better Atmos performance. It supports more wireless playback options. That said, the M Series has a better surround performance. It also has less compression at max volume, so your audio sounds cleaner during louder listening sessions.
The Vizio M Series M512a-H6 is a better soundbar for mixed usage than the standalone Sonos Arc. The Vizio has a better surround performance, and unlike the Sonos, it has a Full HDMI In port and EQ presets. It also reproduces a more extended low-bass thanks to its dedicated sub. The Sonos is better built and has a room correction feature and built-in voice assistant support. You can also upgrade it to the Sonos Arc with Sub + One SL Speakers for better performance.
The Vizio M Series M512a-H6 is slightly better than the Vizio SB36512-F6. The M Series is better built and has better soundstage and surround performances. It also has more sound enhancement features like dialogue enhancement. That said, the SB36512-F6 supports more wireless playback options.
The Vizio M Series M512a-H6 is better for most uses than the Sonos Beam (Gen 2). The Vizio is a 5.1.2 setup with a dedicated sub and satellites. It offers a better surround performance and gets louder with less compression at max volume. Unlike the Sonos, it even has a Full HDMI In port for high-quality passthrough. That said, the 5.0 Sonos is better built. Some users may also prefer its smaller, more compact design.
The Hisense AX5125H and the Vizio M Series M512a-H6 are similarly priced 5.1.2 Dolby Atmos soundbars. The Vizio is the better option overall, largely thanks to its improved stereo soundstage performance. Plus, the Vizio has a few more sound enhancement features, and its latency performance is better.
The Vizio M Series M512a-H6 is better than the Vizio V Series V51-H6. The M Series is better built, with better soundstage and surround performances. Unlike the V Series, it supports Atmos content and has a Full HDMI In port.
The Vizio M Series M512a-H6 is better than the Sonos Beam. The Vizio is a 5.1.2 setup with a dedicated sub and satellites. Unlike the Sonos, it supports Atmos content and has a Full HDMI In port for high-quality passthrough. It also gets louder, and it has a better surround performance. The 3.0 Sonos is better built with built-in voice assistant support. Some users may also prefer its more compact design.
Depending on your listening habits, you may prefer either the Sonos Arc with Sub + One SL Speakers or the Vizio M Series M512a-H6. The Sonos is better built, and it has better surround and Atmos performances. Unlike the Vizio soundbar, it has built-in voice assistant capabilities and a room correction feature. However, the Vizio has a more neutral sound profile out of the box, which some users may prefer. Unlike the Sonos, it also has a Full HDMI In port for high-quality passthrough.
The Vizio M Series M512a-H6 is better than the JBL Bar 9.1. The Vizio is a 5.1.2 setup that gets louder with less compression at max volume. Also, it comes with more sound enhancement features, like bass and treble adjustments and dialogue enhancement. However, the JBL is better built with more wireless playback options.
The Vizio M Series M512a-H6 and the Samsung HW-Q800B are both very versatile 5.1.2 setups, so depending on your listening habits, you may prefer one over the other. The Vizio is a more affordable bar with discrete satellites included, so it has a better surround sound performance. It isn't as well-built as the Samsung soundbar and doesn't offer as many features like room correction and voice assistant support.
Depending on your listening habits, you may prefer either the Vizio M Series M512a-H6 or the Bose Smart Soundbar 900 with Speakers + Bass Module. The Bose is a better-built 5.1.2 setup with better soundstage, surround, and Atmos performances. Unlike the Samsung soundbar, it has built-in voice assistant support. However, it doesn't support DTS content like the Vizio and lacks a Full HDMI In port.
The Vizio M Series M512a-H6 and the Sony HT-A7000 with Speakers + Bass Module are both very versatile setups, but the Vizio scores better overall. The Vizio gets louder than the Sony with less compression at max volume. It has a better soundstage and can reproduce a bit more low-bass. However, the Sony has more sound enhancement features and a better surround sound performance.
The Vizio M Series M512a-H6 is better than the Samsung HW-Q700A. The Vizio is a 5.1.2 setup that has dedicated satellite speakers. It reproduces a more extended low-bass, making you feel more thump and rumble in your audio. It also has better soundstage and surround performances. That said, the 3.1.2 Samsung is better built with more wireless playback options. Unlike the Vizio soundbar, it also has a graphic EQ for sound customization.
The Vizio M Series M512a-H6 and the Sony HT-A5000 are two very different soundbar setups. The Vizio is more versatile, and it's a 5.1.2 setup with a dedicated sub and satellites. It reproduces a more extended low-bass and has better soundstage, surround, and Atmos performances. However, the standalone Sony is ideal if you don't have a lot of space in your living room. It has more sound enhancement features than the Vizio, and you can upgrade it with a sub and satellites if you want.
The Vizio M Series M512a-H6 is better than the Vizio SB46514-F6. The M512a-H6 has a better stereo soundstage and has more sound enhancement features, including dialogue enhancement. That said, the SB46514-F6 is better built with more wireless playback options.
The Samsung HW-Q950A is better than the Vizio M Series M512a-H6. The Samsung is an 11.1.4 setup that gets louder with less compression at max volume. It has better surround and Atmos performances and supports more wireless playback options. It has more sound enhancement features like room correction and a graphic EQ. Its voice assistant support is built into the bar, whereas you need a third-party voice assistant-enabled device to use them with the Vizio. That said, the Vizio offers a better stereo soundstage.
The Vizio M Series M512a-H6 is better than the Vizio V Series V51x-J6. The M Series is a better-built setup that supports Dolby Atmos content. It has better soundstage and surround performances. Also, it can reproduce a more extended low-bass.
The Vizio M Series M512a-H6 is better than the onn. 42" 5.1. 2. Dolby Atmos Soundbar. The Vizio is a 5.1.2 setup with discrete satellites and has better surround and Atmos performances. Its soundstage is better, too, and unlike the onn, it has DTS support.
Depending on your listening habits, you may prefer the Vizio M Series M512a-H6 or the standalone Bose Smart Soundbar 900. The Vizio comes with a sub and satellites, and unlike the Bose, it even has a Full HDMI In port for high-quality passthrough. It also offers a better surround performance. However, the Bose is better built with a better Atmos performance. You can also upgrade it with a sub and satellites if you prefer.
The Vizio M Series M512a-H6 is slightly better for mixed usage than the Samsung HW-Q800A. The Vizio is a 5.1.2 setup that has discrete satellite speakers. It has better surround and soundstage performances. The 3.1.2 Samsung is better built with more wireless playback options. Unlike the Vizio soundbar, it has voice assistant support built into the bar and a graphic EQ to customize its sound.
The Vizio M Series M512a-H6 is better than the Polk Audio Signa S4. The Vizio is a 5.1.2 setup with discrete satellites offering better soundstage and surround performances. It can reproduce a more extended low-bass than the Polk, too. Unlike the Polk, it has DTS support and a Full HDMI In port for video passthrough. If you don't have space for satellites in your room, the Polk is still a fair option with Dolby Atmos support.
The Vizio M Series M512a-H6 is better than the LG SP7R. The Vizio supports Dolby Atmos content, unlike the LG. It gets louder, too, and reproduces a more extended low-bass. You don't have to wire its satellites to a receiver, which some users may prefer.
The Vizio M Series M512a-H6 is better than the Polk Audio MagniFi MAX SR. The Vizio is better built, and unlike the Polk Audio, it supports Dolby Atmos content. This 5.1.2 setup also has better soundstage and surround performances.
The Vizio M Series M512a-H6 is better than the Samsung HW-Q65T. The Vizio supports Dolby Atmos content and has a better stereo soundstage. It also reproduces a more extended low-bass. However, the Samsung comes with a graphic EQ for sound customization, unlike the Vizio.
Depending on your listening habits, you may prefer either the Samsung HW-Q900A or the Vizio M Series M512a-H6. The Samsung is a 7.1.2 setup with more wireless playback options and sound enhancement features, like room correction. It gets louder and has built-in voice assistant support. That said, the 5.1.2 Vizio comes with discrete satellites. It has better soundstage and surround performances, too.
The Vizio M Series M512a-H6 is better than the Samsung HW-Q600A. The Vizio has discrete satellites and offers a better surround performance. It also reproduces a more extended low-bass and has a better soundstage. The Samsung is better built, though.
The Vizio M Series M512a-H6 is better than the Samsung HW-Q800T. The Vizio is a 5.1.2 setup with satellites. It has better soundstage, surround, and Atmos performances. That said, the 3.1.2 Samsung is better built.
The Vizio M Series M512a-H6 is a bit better for mixed usage than the LG SP9YA. The Vizio has discrete satellites and a better surround performance. It also has better stereo soundstage and center channel performances. That said, the LG is better built with more wireless playback options. It also comes with room correction, unlike the Vizio.
The Vizio M Series M512a-H6 is better than the Vizio M-Series M21d-H8R. The M512a-H6 is a 5.1.2 setup with a dedicated sub and satellites. It can reproduce a more extended low-bass and has better surround and soundstage performances. It even has Dolby Atmos support, unlike the standalone M21d-H8R.
The Vizio M Series M512a-H6 is better than the Sony HT-G700. The Vizio is a 5.1.2 setup with dedicated satellites. It has better soundstage, surround, and Atmos performances, and it gets louder with less compression at max volume. Also, it can reproduce a more extended low-bass.
The LG SN11RG and the Vizio M Series M512a-H6 offer similar overall performances. The Vizio is a 5.1.2 setup with better soundstage, center, and surround performances. The 7.1.4 LG is better built with more sound enhancement features, such as room correction. It also supports more wireless playback options.
The Vizio M Series M512a-H6 is better than the Sony HT-Z9F. The Vizio has discrete satellites and better surround and Atmos performances. Also, it can reproduce a more extended low-bass out of the box. It even has a better soundstage.
The Vizio M Series M512a-H6 is better than the JBL Bar 5.1 Surround. The Vizio has discrete satellite speakers and better soundstage and surround performances. Unlike the JBL, it also supports Dolby Atmos content. That said, the JBL is better built with more wireless playback options.
Depending on your listening habits, you may prefer either the Vizio M Series M512a-H6 or the Samsung HW-Q850A. The Vizio is better built, with a more neutral sound profile out of the box. It also has a better stereo soundstage and center channel performance. However, the Samsung soundbar has better surround and Atmos performances. It has a graphic EQ and built-in voice assistant support. It also supports more wireless playback options.
The Vizio M Series M512a-H6 is better than the Samsung HW-Q59CT. The Vizio supports Dolby Atmos content and has better soundstage, center, and surround performances. Unlike the Samsung soundbar, it comes with discrete satellite speakers. It also reproduces a more extended low-bass. However, only the Samsung soundbar has a graphic EQ, which some users may prefer for sound customization.
The Vizio M Series M512a-H6 is better than the LG SP8YA. The Vizio is a 5.1.2 setup with discrete satellite speakers offering a better surround performance. It also has a better stereo soundstage. That said, the 3.1.2 LG has more wireless playback options and a room correction feature.
The Vizio M Series M512a-H6 and the Samsung HW-Q950T are both very versatile setups, so depending on your listening habits, you may prefer one over the other. The Vizio is a more budget-friendly pick with a better soundstage. However, it doesn't get as loud as the Samsung, and its surround sound performance isn't quite as impressive. The Samsung also has a graphic EQ, so you have more ability to customize its sound.
The Samsung HW-Q930B is better than the Vizio M Series M512a-H6. The Samsung is a more premium Dolby Atmos soundbar and better built overall. Its surround and Atmos performances are better, so sound effects are more accurate in the mix, and it also comes with more sound enhancement features. However, the Vizio is a good option if you're looking for an immersive sound at a more affordable price. It even has a better soundstage than the Samsung soundbar.
The Vizio M Series M512a-H6 is better than the Klipsch Cinema 600. The Vizio is a 5.1.2 setup that comes with discrete satellites. It's better built and has better soundstage, center, and surround performances. Unlike the Klipsch soundbar, it also supports Atmos content and has a Full HDMI In port for high-quality passthrough. There are even some additional sound enhancement features available like EQ presets.
The Vizio M Series M512a-H6 is better than the Polk Audio Signa S2. The Vizio is a 5.1.2 setup with discrete satellites. It can reproduce a more extended low-bass, and unlike the Polk, it supports height content. Its soundstage, center, and surround performances are better, too.
Test Results
The Vizio M512a-H6 has a simple design. It's mostly made of plastic draped with fabric. In the middle of the bar, there's a metal grille protecting the two up-firing speakers.
The sub is mostly made of melamine, and the top is made of plastic. It sits on four plastic pegs with rubber grips.
The satellites are mostly made of plastic. There's fabric covering the front and the sides. They need to be wired to the sub to work. If you don't have space in your setup for satellite speakers, you may prefer a different Atmos setup like the Polk Audio Signa S4.
Due to its width, the Vizio M512a-H6 doesn't fit between the legs of most 55" TV stands. That said, it isn't very tall, so it doesn't block your TV screen unless your TV sits flush on the table.
The sub is the same size as the sub for the Vizio M Series M51a-H6. It's a bit shorter than the average desktop PC.
The satellites are fairly small. They need to be wired to the sub to get them to work, but they don't require a power cable, which is handy.
The Vizio M512a-H6 has a good build quality. The bar is mostly made of plastic, which feels solid and durable, and there's a metal grille on the top middle of the bar to help protect the up-firing speakers. The sides of the bar are draped with a tight fabric, though this could collect dust easily. The sub is mostly made of melamine with a plastic top. The satellites are also mostly made of plastic, with fabric covering the front and the sides.
- Manuals
- Wall mounting template
- 4x wall mount brackets
- 4x wall mount screws
- 4x cable ties
- Remote with batteries (2x AAA)
- Optical cable (4.9 ft / 1.5m)
- HDMI cable (6.2 ft / 1.9m)
- 2x audio cables for surround speakers (26 ft / 8m)
- 3.5mm to 3.5mm audio cable (4.9 ft / 1.5m)
- Stereo RCA to 3.5mm audio cable (4.9 ft / 1.5m)
- Power cable for sub (8.5 ft / 2.6m)
- Power cable for bar (4.9 ft / 1.5m)
The Vizio M Series 5.1.2 has a very good stereo frequency response. The manufacturer recommends that you place the subwoofer beside the couch, so we placed it there in our tests. Overall, the sound profile is pretty balanced, with a slightly v-shaped sound due to the extra punch in the bass and sparkle in the treble. With balanced mids, voices and lead instruments are clearly and accurately reproduced. You can also customize its sound a bit with its included bass and treble adjustments.
The Vizio M Series 5.1.2 comes with bass and treble adjustments so you can customize its sound profile. However, if you prefer a more neutral sound profile, its default settings already have a slope within the ideal range.
The Vizio M Series 5.1.2 Soundbar has an impressive stereo soundstage performance. Its soundstage is perceived to be a bit wider than the bar itself, and its focus is very good. It's easy to pinpoint sound objects like voices and footsteps to an accurate location in the sound image.
The Vizio M Series 5.1.2 has an impressive stereo dynamics performance. The bar gets pretty loud, and there isn't a lot of compression when you push it to max volume. As a result, it's suitable for listeners who like to crank up the volume to fill up large spaces and crowded parties since your audio remains clean at loud volumes.
The Vizio M Series 5.1.2 Soundbar has an excellent center channel performance. It comes with a discrete center channel which helps to more accurately localize voices within the sound image. It also has a neutral frequency response that's balanced in the mid-range, so vocal-heavy content like dialogue reproduces clearly and accurately. Updating the bar to firmware version 2.1.0.4 makes little difference in its center channel performance.
The Vizio M Series 5.1.2 Soundbar has a good surrounds performance. It has discrete surround speakers, so sound effects are clearly and accurately represented in the soundstage. Audio seems to be coming from all around you rather than just from speakers placed in front of you. Its frequency response is also slightly bass-heavy, so your audio content packs a little extra thump and punch. Updating the bar to firmware version 2.1.0.4 makes little difference in its surround channel performance.
The Vizio M Series Soundbar comes with two up-firing speakers built into the bar itself, which bounce sound off the ceiling and back down towards you to create the illusion of height. It's not quite as immersive as home theater setups with down-firing speakers on the ceiling, but it does better than soundbars without up-firing drivers, like the Vizio M Series M51a-H6. Sound effects are fairly clear in the mix, thanks to its balanced mids. You notice a little less rumble in the bass, especially with action-focused scenes like explosions and car chases. Updating the bar to firmware version 2.1.0.4 makes little difference in its Atmos performance.
Subjectively, the Vizio M Series 5.1.2 Soundbar performs well for its price, offering a fairly immersive sound, especially for average-sized living rooms. You don't have any trouble following the action on your screen, and the satellites add a nice touch, as sound effects seem to stretch the space around you. Compared to more premium setups like the Vizio Elevate, the bar doesn't achieve as much height. It doesn't seem like helicopters fly right over your head, for example. Instead, these sound effects just seem to come from the space in front of you. If you're willing to pay a little more, you can check out the Vizio M Series Elevate M512E-K6, which has rotating drivers to enhance the listening experience with Dolby Atmos content.
The Vizio M Series Soundbar has a decent selection of sound enhancement features. You can customize its sound using its EQ presets: 'Direct', 'Movie', 'Music', and 'Game'. Stereo files play from the bar and the subwoofer on all four EQ modes. When you play surround files on 'Direct' mode, audio plays from the subwoofer and the satellites. When you play surround files on 'Movie, 'Music', or 'Game' mode, audio plays from both the bar, the subwoofer, and the satellites.
The Vizio M Series 5.1.2 has a dialogue enhancement feature to make voices more clear and crisp and a night mode feature that helps balance the volume level across different programs. Unfortunately, compared to the Samsung HW-Q800B, it lacks more premium sound enhancement features like room correction, so it sounds different depending on the room you're listening in. You can still use its bass and treble adjustments to make up for this a bit, though.
The Vizio M512a-H6 comes with several physical inputs. There's a Full HDMI In port, meaning you can use it as a hub between different devices. However, even though the bar comes with a 3.5mm to RCA cable, there isn't an RCA In port, which can be disappointing if you want to use that connection to link your bar to your TV.
The Vizio M Series Sound Bar has incredible audio format support via ARC. It supports many formats, including Dolby Digital, the most common surround sound format. It also supports lossless and object-based formats like DTS:X and Dolby Atmos.
The soundbar also supports PCM content. In our tests, we send an audible cue to each individual channel to see if it's active. When you listen to PCM content on the Direct sound mode, you ultimately get a 5.1 setup, with sound coming from the left and right channels on the bar as well as the left and right satellites. If you switch to any other sound mode, these same channels are active, as well as the left rear and right rear surrounds, which play on both the bar and the satellites. However, with any sound mode other than direct, you miss out on the thump from the sub, as there isn't any audio confirmation for LFE.
The Vizio M512a-H6 also has fantastic audio format support via Full HDMI In. It supports Dolby Digital and DTS, which are commonly found on Blu-ray discs and streaming platforms. Also, it supports more premium object-based formats like DTS:X. However, like ARC/eARC, the bar supports PCM, but it won't produce left and right rear surround if you're on 'Direct' sound mode. If you're on a different mode, left and right rear surround will play on both the bar and satellites. However, there's no audio confirmation for LFE.
The Vizio M512a-H6 supports both Dolby Digital and DTS via Optical, which is handy for listeners who watch lots of Blu-ray discs and content from streaming platforms.
Latency is excellent over an ARC connection. It falls within good limits for many different audio formats commonly found on both streaming platforms and Blu-rays, so you don't have to worry about lip-synching issues. Some apps and TVs compensate for latency differently, though.
The Vizio M Series M512a-H6 has low latency over HDMI In, too. The audio you hear is in sync with the video on screen when you watch lots of common audio formats, from Dolby Digital to Dolby Atmos. Latency can vary a bit based on the apps and TV you use, though.
Over an Optical connection, you get low latency with 2.0 PCM content. Latency is a little higher with Dolby Digital content though, so you notice some lip-sync delay. Unfortunately, there aren't any tools included to manually adjust for this.
The Vizio M Series Sound Bar can passthrough the highest bandwidth signals. When connected between your PC and your TV, text on the screen appears clear and crisp.
The Vizio M Series Sound Bar lets you wirelessly stream audio from your mobile devices to the bar via Bluetooth.
This soundbar doesn't have an interface. Instead, a series of vertical lights on the left side of the bar flash different patterns depending on the settings you control. There's also some voice audio feedback when you change between one of the preset modes or change the input.
On top of the Vizio M Series Soundbar, there are physical controls that let you power the bar on/off, change the input, activate Bluetooth pairing, and adjust the volume.
The remote is fairly simple and lets you control all of the bar's functions. It even comes with a display screen.
The Vizio M Series Sound Bar has an AUX VA In port that lets you connect voice assistant-enabled devices like an Amazon Echo to the bar. However, this isn't considered built-in support since it requires that you purchase a third-party device.