Vizio S2121w-DO Sound Stand - Review

Vizio Takes A Stand On TV Sound

Vizio S2121w-DO Sound Stand - Front and Rear View
Vizio S2121w-DO Sound Stand - Photo of the Front and Rear View. Photo © Robert Silva - Licensed to

Dateline: 08/18/2014

Sound Bars are definitely one way to get better sound for your TV for those that just don't want to put up with the clutter of a lot of speakers. However, sometimes even a sound bar might take up too much space - so a similar concept is also becoming popular as an alternative, the "under-TV sound system" approach.

The difference between the Vizio S2121w-DO and its sound bar cousins is that it can not only serve as the audio system for the TV but can be used as a platform to set the TV on top of. This approach not only saves space but looks more attractive than a sound bar sitting in front of the TV.  Vizio refers to the S2121w-DO as a Sound Stand.

Product Overview

Here are the features and specifications of the Vizio S2121w-DO Sound Stand.

1. Design: Bass reflex pedestal design with left and right channel speakers, subwoofer, and one rear mounted port for extended bass response.

2. Main Speakers: Two 2.75-inch full-range drivers.

3. Subwoofer: One 5.25-inch downfiring driver.

4. Frequency Response (total system): 55 Hz – 19 KHz

5. Frequency Response (subwoofer): 55 Hz – 100 Hz

6. Amplifier Power Output: Information not provided.

7. Audio Decoding: Accepts Dolby Digital or DTS Bitstream audio, uncompressed two-channel PCM, analog stereo, and compatible Bluetooth audio formats.

8. Audio Processing: DTS TruSurround HD) and TruVolume

9. Audio Inputs: One digital optical One digital coaxial, two sets of analog stereo inputs (one set RCA-to-RCA and one set of RCA-to-3.5mm), one USB port (provided for both service and playing back WAV files on compatible flash drives), and wireless Bluetooth connectivity.

10. Control: Both onboard and wireless remote control options provided.

11. Dimensions (HWD): 4 x 21 x 15-1/2 inches.

12. Weight: 10lbs.

13. TV Support: Can accommodate LCD and Plasma TVs up to 55-inches in screen size with a maximum of 60-pound weight (as long as the TV stand is not larger than the S2121w-DO platform dimensions).

Set-up and Performance

For audio testing, the Blu-ray Disc and DVD players I used (OPPO BDP-103 and DV-980H) were connected to the TV via HDMI outputs for video, and both the digital optical and RCA stereo analog outputs were alternately connected from the players to the the S2121w-DO.

To make sure that the reinforced rack I placed the Sound Stand on was not affecting the sound coming from the TV, I ran a "Buzz and Rattle" test using the audio test portion of the Digital Video Essentials Test Disc and there were no audible issues.

In listening tests conducted with the same content using both the digital optical and analog stereo input options, the S2121w-DO provided good sound quality.

The Vizio S2121w-DO did a good job with both movie and music content, providing a well-centered anchor for dialog and vocals, despite the lack of a dedicated center-channel speaker.

The S2121w-DO does well as a straight two-channel stereo playback system if you prefer listening to your CDs or other music sources in a traditional two channel setup. However, the one thing you will notice in two-channel stereo mode is that the left and right soundstage is rather narrow. I found that the wider soundstage when the DTS TruSurround HD feature was engaged added both depth and a wide soundstage for music-only listening that was beneficial.

Using the audio tests provided on the Digital Video Essentials Test Disc, I observed a listenable low point of about 40Hz to a high point of at least 17kHz (my hearing gives out at about that point). However, there is faint audible low-frequency sound as low as 35Hz.

I found that the S2121w-DO is definitely loud enough, and if you put your hand over the rear port there is a lot of air being pushed out. Vizio no longer provides actual wattage output specs, but I can definitely say that it had no problem providing a good listenable experience in my 15x20 room.

However, the low-frequency effects, although deep when you consider the size of the unit, were not that well textured. Also, there was a definite boost between 60 and 70Hz, which contributed to a slight boominess on effects-heavy soundtracks. Using the S2121w-DO s bass and treble controls, you can adjust the overall output level of both the low and high frequencies, but as you lower the bass level you do lose the deep-end effect that is desirable for movie viewing.

Moving to the mid and high-end of the sound spectrum, the S2121w-DO provided a clear midrange, which served both movie dialog and music vocals well, in terms of presence, but without incorporating separate tweeters, high frequencies, although undistorted, were a little dull. For example, on movies scenes with lots of flying debris or transient background elements, or music tracks with percussive effects, those sounds are subdued, or, in the case of very fine low volume background sound, sometimes lost, resulting in a less dramatic listening experience.

With regards to audio decoding and processing, it is important to point out that although the S2121w-DO does provide Dolby Digital decoding and DTS audio processing (TruSurround HD and TruVolume), it does not accept or decode incoming native DTS-encoded bitstreams that are passed through a digital optical or digital coaxial audio connection.

This means that when playing a DVD, Blu-ray, or CD that may only provide a DTS soundtrack (rare these days - but may still be encountered), you must set your DVD or Blu-ray Disc player to PCM output. If you want to access onboard decoding for Dolby Digital-encoded content, you need to reset your source to output in Bitstream format (if you are suing the digital optical/coaxial connection options - if using the analog audio connection option, keeping your source setting on PCM or changing it to Dolby Digital does not make a difference as only the PCM output is passed through the analog audio outputs).

What I Liked

1. Good overall sound quality for the form factor and price.

2. The design and size of the sound stand form factor match well with the appearance of LCD and Plasma TVs.

3. Wide soundstage when DTS TruSurround HD is engaged.

4. Incorporation of wireless streaming from compatible Bluetooth playback devices.

5. Recessed and clearly labeled rear panel connections.

6. Very quick to setup and use.

7. Can be used either as an under-TV audio system or a standalone stereo system for playing CDs or music files from Bluetooth devices and USB flash drives.

What I didn't Like

1. No HDMI pass-through connections.

2. No tweeters to extend high-frequency detail.

3. Needs more tightness on the low end.

4. No real front panel status display, except for a couple of blinking LEDs - makes it difficult to know how you have set the volume levels and what input source you have selected (you need to remember the LED display pattern for each selection).

5. Can only play .WAV files from USB source devices.

6. USB port located on the back of the unit, instead of on the side or the front, which makes it inconvenient for plugging in USB flash drives temporarily to listen to stored music files.

Final Take

Vizio has made the jump into the "under TV" sound system category, and after spending some time listing, I feel they are off to a good start.

The main challenge of taking the characteristics of a sound bar and placing it into an even narrower horizontal form factor is the delivering of a wide sound stage. The Vizio S2121w-DO, in out-of-box stereo mode definitely has a narrow soundstage with very little sound projected beyond its left and right borders - However, once you engage DTS Surround HD audio processing the sound stage does widen considerably both horizontally and slightly upwards, which give the listener the impression that sound is coming from the TV screen and not below it, and also provides a "wall of sound" across the front of listening area.

As it is currently equipped the Vizio S2121w-DO provides a good alternative to both a TV's built-in speakers, as well as a soundbar, if you have space limitations (no need to place a separate subwoofer in the room). It is definitely worth consideration if you are looking for something compact to provide an improved listening experience for your TV view in.

On the other hand, I think that with a couple of tweaks, such as adding a tweeter to both the left and right channels, as well as taming the subwoofer so that is it just a little less boomy in the mid-bass range, the S2121w-DO would not only provide more accurate sound, but with Vizio's value-priced structure, separate it further from its competition.

For a closer look and perspective, also check out my supplementary Photo Profile.