Story by Caleb Denison, via our partner site, Digital Trends /
Surround sound is one of the coolest features of an epic home theater system. After all, who doesn’t want earth shattering, immersive sound to enhance that brand new 4K Ultra HD TV sparkling on your entertainment stand? For those without an audio degree, however, surround sound can get complicated quickly. With multiple formats, acronyms for days, and a plethora of components and delivery methods to choose from, it can all be a bit overwhelming.
But never fear, we’re here to clear up the haze with a short and sweet guide to all things surround sound. So follow our video above, sit back, and get ready to enjoy your surround sound future.
Speaker Placement & Configurations
Stereo sound is perhaps the most common home audio configuration, easily recognized as two speakers set to the left and right of your TV that combine for a what’s considered a 2.0 system in the home theater world. Surround sound begins when you add a third element for 3.0 sound via a center channel speaker lined up just below your TV. When it comes to home theater, the center channel is your best friend as it handles a majority of the sound — including all the dialogue — which makes the center speaker a great place to splurge.
The next component on the list is the LFE channel, or subwoofer channel. A subwoofer handles low-frequency sound (the booms and rumbles), and is represented in our surround sound configuration as the “.1” portion; add a subwoofer to our 3.0 setup and you get 3.1 surround sound. Some high end systems actually add a second subwoofer to the equation, which would be a 3.2 setup, but for most users a single subwoofer will suffice. As low-frequency sound is less directional a subwoofer can be more freely positioned in your setup, though you’ll want to keep it a fair distance from parallel surfaces like walls and corners.
Next up are the surround speakers, often called satellite speakers. If you want true, immersive surround sound, adding at least two surround speakers into the mix is necessary. This pushes our setup to 5.1, the most common surround sound configuration. The main surround speakers will be positioned to the side and just behind the main listening area, faced toward it. Adding two more surround sound speakers to the back of the room (faced toward the screen) brings even more immersion for 7.1 surround. And while that number stretches even further (essentially maxing out at 11 discrete, full-frequency channels), most listeners will find 5.1 surround suffices for the majority of applications.
That said, there are two newer surround sound formats that have become very popular in recent years which literally take your surround sound experience to the next level.
Dolby Atmos and DTS:X surround sound formats add in height channels to our surround sound configuration, aimed at totally engulfing the listening area in a hemispheric globe of sound. These speakers can be mounted above the listening area in the ceiling, or you can buy Atmos enabled speakers that project sound up at the ceiling to bounce sound down to the listening area. Depending on your receiver’s capability, you’ll most commonly see the height channels of these new formats as a “.2” (meaning two height channels) or, at the maximum, “.4” (meaning four height channels), which would push our basic 5.1 system to 5.1.2 or 5.1.4 respectively.
Speaking of Dolby and DTS, these are the names you’ll hear over and over again when it comes to surround sound formats, though there are others. Dolby and DTS make the primary digital sound signals that go to your receiver or soundbar system. Within that digital signal are instructions as to which sound channels go to which speakers. There are several main types of signals produced by Dolby and DTS which vary by quality and source.
The best sound quality will come from Dolby True HD or Dolby Atmos surround sound signals, or DTS HD Master Audio and DTS:X. These are the cream of the crop, and are most commonly found on Blu-ray discs. That’s because Blu-ray is able to hold more information than other video hardware. As mentioned above, Dolby Atmos and DTS:X represent the highest sound quality with the most immersive surround channels.
Streaming from Netflix and other services usually sits somewhere in the middle, often utilizing Dolby’s Digital Plus signal. It still sounds great, but the quality isn’t quite as the formats mentioned above. Dolby Atmos began trickling into streaming services in 2017, but it’s still a rarity to find it there at this point.
At the bottom of the rung are basic Dolby Digital and DTS, which are most commonly found on good old DVDs. Again, the audio from these signals will still sound good on your system, but it won’t be as dynamic or clear as the top-tier surround sound signals.
When it comes to delivering all that surround sound action, you can always go with a full, multi-component speaker and receiver setup, but soundbars have come a long way on the surround sound front in recent years. For those who want to save space (and money), soundbars may be a good option for surround sound.
Some soundbars utilize digital surround sound, often known as virtual surround sound. This means the soundbar uses digital processing to make it seem like sound is coming from behind or around you. Others use a more traditional approach, adding in satellite surround speakers to the equation, or even height channels that bounce sound off the ceiling for Dolby Atmos or DTS:X surround sound. The primary three channels (left, center, right), are almost always located within the soundbar itself, often with a wireless subwoofer to fill out the low end sound.
If you want the best sound, you’ll want to spend the money — and the floor space — on a traditional surround sound system composed of a receiver and multiple speakers. That said, for many listeners a soundbar may be the best compromise. It all depends on how important surround sound is to you, and how much space (and money) you’ve got on hand.
Whichever option you choose, you should now be fully equipped to dive into the wide world of surround sound. Now it’s time to go out there and find the system that’s right for you!