The transcendent world of surround sound is here to stay. While thousands have enjoyed a surround mix at the movie theater, mixing studio recordings across more than two channels is becoming more common, so it's definitely worth understanding as a producer or engineer.
Surround sound production provides you with an entirely new, expanded sound field to help your listener immerse him or herself in the music, but the limitless possibilities can be understandably overwhelming.
Fortunately, we've put together a complete guide to crafting a surround mix so that you can sharpen your skills and build lively, transcendent mixes. Below, we'll break down everything you need to know about surround sound and share some essential dos and don'ts so that you can start experimenting with this novel mixing method.
Understanding Surround Sound
As the name suggests, surround sound is a type of sound design in which the goal is to immerse the listener in audio, rather than placing the sound in a more fixed location as with a mono or stereo mix. This audio technique accomplishes this by utilizing multiple sound channels to recreate sound, placing speakers or monitors at several points around a listener.
Surround environments can easily act as a more immersive audio environment for listeners. In the world of film, surround sound design has been widely adopted for several decades, though its use within consumer audio is fairly novel. There are several types of surround sound, though 5.1 is arguably the most recognizable as of fall of 2023.
Stereo Mixing Versus Surround Mixing
Stereo and surround mixes can both be used to enjoy music, but are otherwise very different. In a stereo setup, you experience through two speakers, or left and right channels. With surround mixes, the number is much higher, varying based on the version of surround sound.
A stereo mix is consumed as though the sound is slightly in front of the listener, whereas surround sound is designed to surround the listening position from as many angles as possible. While surround sound design was originally intended for movies and television, it is increasingly making its way into the consumer audio world, finding its place with music in spaces like Apple Music with the Dolby Atmos collaboration.
What Are Surround Channels?
Surround channels refer to the number of monitoring speakers distributing a signal across an audio field. This number will vary based on your chosen version of surround sound. For example, Dolby Atmos, 5.1 surround sound, 7.1 surround sound, all have various surround channels to create different listening experiences.
What is the difference between a 5.1 and 7.1 mix?
As the surround format will tell you, the number on the left of the "." stands for the amount of speakers used in addition to the LFE channel represented by the "1" on the right of the period. So, 5.1 surround sound uses 6 surround channels in total while 7.1 surround uses 8.
5.1 surround sound is probably the most commonplace version, but it's worth understanding the wide variety of surround sound configurations. Check out Audio University's high level overview of surround sound formats:
How Do You Mix In Surround Sound?
Mixing in surround sound is much like mixing in any other environment, except instead of feeding your signal to the left and right speakers, you're separating your sound across six or eight channels for a more immersive effect. This can also be done utilizing a virtual mixing room as shown in the tutorial below.
Check out the renowned engineer Simon Vinestock's basic tips on mixing in surround sound:
Ensure that your chosen auxiliary busses are aligned with your particular version of surround sound. If you're using a virtual mixing room for your surround mixing tasks, you'll need to set up an additional send bus on your master channel to effectively feed your mix through a surround mixing environment as shown. In the case of Waves' NX, you'll need to select your headphones output within the plugin itself before diving deep into your session.
Keep in mind that you may be limited based on your software of choice - since surround 5.1 and 7.1 mixing are both fairly new endeavors, you might not have access to these features depending on your inventory.
Note that in many cases, you'll still create a stereo mix alongside a surround sound mix. For instance, in Apple Music, you have the option to toggle surround mixing on or off as the listener for eligible tracks. Surround mixing is not a replacement for stereo mixing, but it can create a different sonic environment.
The surround sound center channel will lie more or less in the same place as the stereo phantom center, for instance, but the additional two rear speakers, side channels, and LFE channel introduce a whole host of new variables that lend themselves best to an entirely separate mixing session.
For a more in-depth tutorial, check out this overview by composing group Crow Hill Company:
How To Set Up Surround Mixing Monitors
The way you set up your surround mixing monitors will depend heavily on your chosen surround set up. In this case, we're going to assume you're optimizing for a 5.1 surround sound mix. The engineer should be placed in the center of all monitoring speakers, equidistant from each in an area called the "sweet spot."
The center channel monitor should stand directly in front of you, with the front left and right speakers aimed about 30 degrees angled towards the sweet spot. The surround left and right speakers should be placed at 110 degrees left and right from the sweet spot. Finally, the the LFE should be situated front and center.
Consider this tutorial series on how to build a surround speaker setup in your studio:
5 Surround Sound Production Tips
While surround sound mixing is a relatively new discipline, there are some general pointers to keep in mind when you're mixing within a surround sound field:
Consider the Context
A surround mix for film is going to have several considerations that you won't find for a mix intended for casual music listening. For instance, a film surround mix should have space carved out for dialogue to help the score gel more effectively within the world of the story. Before you start any surround mix, consider the intended audiences and playback devices.
Don't Overuse the LFE Channel
The low-frequency effects channel is impactful, especially in a theater-like environment. However, with great power, comes great responsibility. The LFE feeds right into the subwoofer channels of a system, so overuse can easily cloud the entire mix. Save the LFE channel for short moments where you want to add a little extra contrast to the mix, if any. It should not be confused for a channel dedicated to bass management.
Take Input/Output Setup Seriously
Remember that most DAWs are still optimized for plug-and-play mixing on left and right channels, not surround sound spread across front speakers and rear speakers. Take the time to curate a session preset that has all the necessary busses so that you can effectively get into the surround sound field. For instance, check out this in depth tutorial on creating a surround mix environment in ProTools:
Check Your Mix In Different Spaces
When mixing stereo recorded music, we're used to checking our mixes predominately in the center image "sweet spot" while we're in the studio. When monitoring surround mixes, it's important to move around to test the listening position from several vantage points.
Lean Into The Distance
Create realistic spatial effects by taking a sampled sound and placing it in multiple spaces across your mix. For instance, maybe you take a raw synth and place it toward the phantom center image of your mix. Towards the rear of the mix, you can place the synth, but this time processed with reverb or even pitched down a couple of semitones. Processing a sound slightly differently in several locations can have some pretty cool results and lead to more of a simulation of true space.
Surround Sound Mixing FAQs
As a new technology, surround mixing understandably poses a lot of questions. Here are some frequently asked questions and answers to help you get to the bottom of surround mixing:
Is surround sound good for mixing?
You should always mix according to your intended sound output. Stereo mixes should be mixed in a stereo environment, whereas creating surround mixes requires engineering with surround sound production speakers to monitor and tame the sound properly.
How is surround sound mixed?
Whereas your basic stereo mix has two channels, a surround sound is mixed with six channels or eight channels depending on the version of surround sound. To mix surround sound, the engineer must place monitors as they would in a full surround mix facility, or use a virtual mix room like Waves Nx to emulate the surround mixing environment.
What is 5.1 mixing?
5.1 mixing refers to a type of surround sound, which is most commonly used in home theaters. With 5.1 mixing, the sound is processed through six speakers, with five full range speakers positioned towards the central listening position and a single LFE channel or low frequency effects channel.
What is creative mixing in 5.1 surround?
5.1 surround sound mixing gives you much more liberty to create realistic spatial effects than sound processed through stereo speakers. You can play with a listener's sense of position and depth for instance, especially as it pertains to sound placed on the side and behind the central listening position.
What is the difference between stereo and surround sound mixing?
Stereo mixing entails separating sound across just two speakers, creating a sense of space between the left, right, and center audio field. Surround mixing creates a more impressive surround field, with sound design also focused on the rear and sides of the subject.
How to convert stereo to 5.1 surround sound?
Ideally, you create a separate surround sound mix using surround speakers in addition to a stereo mix. If you're in a pinch and don't have access to all of your original project stems, you can use a plugin like UM226 to help convert your stereo mix to a surround mix.
What is surround sound mixing?
Whereas stereo mixing creates a sound field focused on the left and right channels, surround sound mixing takes side and rear speakers into account to create more realistic spatial effects. With the recent developments in consumer technology, surround sound mixes can now be enjoyed using certain headphones.
Surround sound technology is still in its infancy. As engineers, we have the amazing opportunity to now build immersive, surround environments by expanding our sound beyond the traditional two-channel separation.
Hopefully, this guide makes it easier for you to understand the world of surround sound, but the best way to get a handle on something is to experience it for yourself! Have fun building immersive mixes across the surround sound field.