Mono compatibility is a concern that’s at the back of every producer’s mind. Nobody wants to spend countless hours working on a mix that sounds great in stereo but falls apart on mono playback systems. We’ll be taking a look at how you can achieve improved mono compatibility by building your mixes in the shape of a tree.
Choose Between a Narrow Mix or a Wide Mix
You have the ability to manipulate the stereo image of your mix however you like; this ultimately means that there are no rules when it comes to how wide you make your mix, but there are a few things you should take into consideration before making the decision.
Narrow mixes tend to sound focused and impactful, while wide mixes shed some of these qualities in favor of a grandiose sound that potentially allows for higher perceived loudness values.
In general, narrow mixes summed to mono tend to sound more similar to the stereo version of the song than wide mixes summed to mono. Whether the differences you hear sound better or worse is an entirely subjective matter.
In the following song called “Boss Mode” by Knife Party, the main synth and 808 are positioned in the center of the mix, drawing the listener's full attention to the middle of the stereo field. There are still track elements panned out to the sides, but they’re relatively quiet in comparison to the main synth; this indicates to the listener that they’re less prominent song elements.
Compare “Boss Mode” by Knife Party to “Blood” by Illenium and Foy Vance. “Blood” uses a much different arrangement, with the kick panned to the center, and all the main synths panned out to the sides. Instead of all your attention drawn to the center of the stereo field, it’s pulled in multiple directions.
Both of these songs have been executed well, and play back acceptably in mono. Consider using the PreSonus Monitor Station V2 to quickly sum your computer’s audio output into mono with the press of a button; this feature will come in handy all the time when mixing and mastering your music.
I have to give the edge in mono compatibility to “Boss Mode” since the overall track levels remain exceptionally balanced in mono. “Blood” exhibits a loss of energy when summed to mono, which you can hear in the synths; this isn’t to say the “Blood” mix sounds bad in mono, it’s just not quite as alluring as the stereo version of the song in my opinion.
There’s a give and take that occurs when deciding between a narrow stereo mix and a wide stereo mix. Narrow mixes tend to sound similar in mono, whereas wide mixes tend to sound significantly different. However, many people will argue that they really enjoy the sound of widespread stereo mixes. Choosing between a narrow mix and a wide mix is a subjective decision that's ultimately yours to make.
Shape Your Mix into a Tree
In a perfect world, your stereo mix will always sound great when summed to mono, but this isn’t always the case. Phase issues manifest themselves in the form of a loss of energy throughout the frequency spectrum of your song; these issues aren’t necessarily present in stereo, but they can be heard in mono.
Width is created by differences between the left and right channels of an audio file. Unfortunately, phase issues are the result of differences between the left and right channels of an audio file summing together in mono. See the dilemma? How is it possible to create a stereo mix that sums together well in mono?
The low-end of your music, around 0-100 Hz, is the most problematic frequency range when it comes to mono compatibility. If you’ve used a wide stereo sub-bass in your arrangement, it may very well sound fine in stereo, but when summed to mono there’s a huge risk of phase cancellation.
High-end stereo frequency content doesn’t struggle as much to sum together in mono. The period of these high-frequency waveforms is much smaller than low-frequency waveforms, meaning that there’s less potential for phase cancellation.
Turning your mix into the shape of a tree will improve mono compatibility, but what does this mean? You can’t see sound, but your brain can identify the perceived direction from which a sound is being produced. In this way, you’re able to paint an image in your mind of how your mix looks.
Turning a mix into the shape of a tree involves narrowing the low-end of the song and gradually spreading apart track elements as you move further up the frequency spectrum. You can see in the following video, which uses examples from David Gibson’s book called The Art of Mixing, that many mixes use a tree-shaped arrangement.
All of the mixes in the previous video should have no problem summing to mono. They maintain a narrow low-end, and gradually branch out further up the frequency spectrum. Experiment with panning and different stereo imaging techniques to shape your mix into a tree.
Check out ”6 Tips for Creating Wider Mixes” if you need help making your mixes wider. The real challenge isn’t making your mixes wide, but rather, knowing how far to push the width of your mix before your song experiences a significant loss in mono playback quality. Try using a tool like ADPTR AUDIO's Metric AB (Figure 1) to analyze the stereo image of other songs and compare them to the stereo image of your own.
