Surround Sound 101: Everything You Should Know

August 23, 2021

Surround Sound 101

Before we get into the history of surround sound, let’s first take a moment to address how surround sound works. Knowing the basics of this technology may help you understand certain concepts we are going to talk about later on. From there, we can get into where the technology is now.


True to its name, surround sound refers to products and technology that are designed to envelop you in sound from all angles. In its simplest form, speakers are positioned around where the listener is expected to be. Specifically, there is a front center speaker, front left and right speakers, and two speakers placed to the side or behind the central listening position.

In this configuration, the audio system is capable of delivering an immersive audio experience you can’t get from other audio setups.

Matrix Encoding

The way audio is stored and transmitted is known as encoding. In the early days of surround sound, a unique coding process was developed to send separate audio signals to different speakers. This coding process is known as the matrix and was used for Dolby Surround Sound and Dolby Pro Logic.


Dolby Pro Logic used the matrix to create separate signals for the left and right speakers. This enabled media—like VHS—to be multi-channeled. However, the audio that comes from this solution is not in stereo and has limited bandwidth. In other words, both channels play the same sound and don’t include much bass or treble.

The History

Believe it or not, but the creation of surround sound can be attributed to Walt Disney. While the movie Fantasia was still in development, Disney had an idea to make Flight of the Bumblebee a song that could be heard in all directions. According to InformIT, Disney wanted to make it so the “musical sound of the bumblebee could be heard flying all around the audience.” The proprietary technology Disney’s engineers created to make this possible was dubbed Fantasound.

It wasn’t until around 1970 that surround became household technology. The first iteration of home theater surround sound, called Quadraphonic Sound, allowed for four speakers in each corner of the room to play individual audio signals. Quadraphonic Sound is the equivalent to what we now call 4.0 surround sound, more on that later.

About 12 years later, Quadraphonic Sound was replaced by Dolby Surround. The popularity of Dolby Surround incentivized manufacturers to make surround sound devices more affordable and available. Since then, the technology has been pushed further by Dolby, DTS, and other companies.

The Advancement of Surround Sound

The VHS was limited in the amount of audio information it could store, but newer forms of media would help to advance surround sound. For example, the LaserDisc provided much more storage space than a VHS. With this additional space, Dolby was able to create a new format called AC-3, now known as Dolby Digital. This format improved Pro Logic, allowing it to provide higher bandwidth sound, while adding a low frequency effects channel produced by a subwoofer. Dolby Digital made it possible to produce surround sound without the need for matrixing.

5.1 vs 7.1 Surround Sound

Now that you know the basics and history of surround sound, it’s time to discuss the different types of surround sound system setups. You’ve probably heard of 5.1 and 7.1 home theater systems, but what does that mean? The numbers correlate to the number of speakers you have.

As mentioned earlier, Quadraphonic Sound is known as 4.0 surround sound. It’s called that because it uses four different speakers in the four corners of the room. Similarly, 5.1 uses five speakers and 7.1 uses seven. If the surround sound system includes a number with a decimal and number after it, the .1 refers to the subwoofer.

In recent years, we’ve seen the emergence of 5.1.2 and 7.1.2 home theaters. The final number in that sequence states that there are two overhead speakers. So in a 5.1.2 system, you have five speakers on the floor, a subwoofer, and two speakers by the ceiling. Most movies and video games take advantage of this to create what’s known as spatial or 3D audio.

Get the Superb Sound Your Home Theater Deserves

The WiSA Association works with over 70 well-known hardware manufacturers to create WiSA Certified wireless audio devices capable of producing premium sound. From LG to Pioneer and more, we encourage you to visit our partners to find the audio solution your home theater deserves.

If you would like to learn how to choose the best surround sound system, contact us today.

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