As the Director of Audio and Visual Production at Dolby Laboratories in San Francisco, John Loose knows a thing or two about surround sound mixing. Recognized as an expert in the field, he has worked with every variety of surround production from basic 5.1-channel audio mixing to creating complex presentations for Dolby Atmos theater systems with dozens of speakers.
Loose has mixed and mastered hundreds of projects for Blu-ray, DVD, and other media, as well as for feature films. His recent projects include the San Francisco Symphony, Wilco, and the Killers. We recently had a chance to catch up with Loose to discus the basics and best practices for surround sound mixing.
What are the differences between audio-only and music-for-picture surround mixes?
Mixing to picture is all about the dialog, which must be front and center. Off-stage surround effects other than ambiences usually take a supportive role.
If you’re mixing for people who have gone out of their way to procure surround music for their home systems, however, give them something to show off to their friends. Make a surround statement, keeping in mind how your mix will sound played back in multiple surround configurations, such as Dolby Atmos 7.1 or 5.1.
What are the essential tools needed to mix in surround?
The most essential tools are a properly placed and calibrated set of studio monitors and a DAW that has easy surround panning built-in, such as Pro Tools. Calibration gives you a universal starting point, which references a standard set of levels and speaker angles.
There are headphone algorithms that purportedly enable you to mix without surround speakers, but do so at your own risk. Chances are, your mix will not sound right on a high quality, properly calibrated home theater system.
Is it necessary to do anything differently while recording when you’re planning to mix in surround?
If your goal is to reproduce the room in which the music is recorded, it is best to capture the room with dedicated room microphones.
A lot has been written about surround micing techniques. For example, in the classical music world, it is essential to know how to properly capture a room. If you are doing a standard pop mix, on the other hand, you’ll more than likely be using artificial reverb only, so you may end up not needing your room mics.
Also, don’t think only in stereo pairs when preparing a recording meant for surround. The more elements you have to play with, the better.
Describe the placement of instruments, voices, effects returns, and other elements in a typical surround mix.
The beauty of mixing in surround is that you are no longer trying to slice and dice the frequency bands and minimize the dynamic range to squeeze lots of elements into two speakers."
There are no hard-and-fast rules about placement within the surround field, but there are various philosophies. My philosophy – as I often do surround remixes of already popular songs – is to not stray too far from the original stereo mix but to make it bigger and wider with some key surround moments in the mix that make it fun.
I have also found that mixing any essential steady rhythmic element into the surrounds is asking for trouble. In a really big room, the distance between the front and rear speakers can make the song feel rhythmically unstable.
I tend to keep the steady groove in the front and use the surrounds for percussive accents, backing vocals, and for spreading the mix out far and wide.
Which sorts of automation moves tend to work best with surround, and which moves should generally be avoided?
I love snazzy surround pans as much as the next guy, but your brain can only process so much moving sound at once, so I tend to pick my moments and make them big. Too many repetitive swirly pans can be fatiguing.
I do, however, love to place subtle delay returns into the surrounds, even using an auto-panner to make things move between the surround channels. If the mix has no moving elements at all, it will be very static. I want my surround music mixes to really sound like the elements are alive and in motion.
How does the need for applying EQ, compression, and other processing effects differ when you are no longer limited to a 180-degree sound field?
The beauty of mixing in surround is that you are no longer trying to slice and dice the frequency bands and minimize the dynamic range to squeeze lots of elements into two speakers.
When you have more speakers to play with, you will likely find yourself not using as much EQ and compression because the sounds have more chances to live and breathe on their own.
What should one bear in mind when mixing the same material in both surround and stereo for, say, a box set that contains both?
The trickiest things about having stereo and surround in the same package are levels and dynamic range. The CD section will likely be mastered with (at most) 6dB or so of dynamic range, and the Surround version will have a lot more. Because there are no real level wars in surround, most surround music discs will have levels closer to loud TV levels, not loud CD levels.
What should you bear in mind when mixing in surround in terms of front-loading for future playback technologies?
If you’re going to take the time to mix in surround, perhaps you’ll want to archive your work using stems, which are recorded surround submixes of groups of instruments – drums, guitars, vocals, etc. – in both your widest mix format and stereo. This way, you can return to your mix and have a place to start in the future.
Having flattened tracks of your final mix is always handy, too, but keep your originals. While you may not have the plugins you used originally the next time you visit your mix, once you’ve flattened that vocal track with tons of compression on it, there is no way to go back!
About the Author:
Barry Cleveland is a San Francisco Bay Area-based journalist, author, guitarist, and composer. He was an editor at Guitar Player magazine for 12 years and at Mix and Electronic Musician magazines before that. His book, Joe Meek's Bold Techniques is a cult classic, and he also contributed to Whole Lotta Led Zeppelin. He has released five albums, as well as composing music for film, television, and video games.