16 Tips for a Wider, Deeper Mix

As mixing engineers, one of our biggest challenges is communicating width and depth in a stereo track. It’s tricky for loads of reasons. For one, what we’re doing is essentially a fiction: When you listen to Beethoven’s Ninth Symphony on an iPod, you are not at the Philharmonic—yet it’s often the engineer’s job to create the sound of the orchestra, from left to right, front to back, and in the appropriate environment.

Furthermore, the technical concepts we employ to achieve this fiction (dispersion relations, the Haas effect) can be difficult to grasp. Note, too, that mixing is a balancing act, highly relational, with every choice we make inevitably affecting spatial perception.

Of course, you came here for tricks and tips: You want them and you want them now. So rather than inundate you with concepts, I’m going to fire off things that work for me. As always, your mileage may vary.

Nuts and Bolts

1. Depth Isn’t Reverb
Remember that the farther away a sound is from you, the less you’ll hear it. This carries implications in volume and frequency: highs and lows will be muted; the level will be lower. You’ll also hear reflections of whatever space the sound is traveling through.

Thus, to make a guitar sound like it’s coming from down the street, it’s not just a matter of slapping on a reverb. It’s dropping the level, rolling off highs and lows, and then mimicking the reverberant properties of the surrounding space—selecting the right impulse response if working with a convolution reverb; affecting the right calibration of early reflections, late reflections, and pre-delay.

2. Relationships Improve Depth
An instrument or element will sound farther away when contrasted to a more present signal. Your ear, presented with two sounds, will grab onto the one which sounds closer first, and the result is instant depth. It’s like a Bob Ross painting: notice how he’ll push darker mountains into the background by dropping in lighter trees? The example correlates to the audio sphere.

3. Good, Clean Audio Before All
Noisy processors and plug-ins, when piled on, can absolutely obfuscate a mix’s width and depth. For example, a loud and hissy noise floor can mask a quiet, far-away section. Try to minimize the noise of processors wherever possible, especially when they are nakedly apparent. If you’re tied to your noisy, hissy plugs, use automation to mute them when the track isn’t on, or print the affected track and lower the clip-gain on sections that need definition in the space department (the latter will save CPU).

4. Compression Can Be the Enemy of Depth
Downward-compression squashes dynamics, bringing louder signals to a lower level; when we raise the output gain to compensate, the lower-level sounds become louder. The net effect: Across many tracks, too much compression brings sounds closer to you, and can even produce a flattening effect. This is the opposite of depth.

Use compressors to emphasize or tame dynamics on tracks that need the work (or employ a compressor as a color piece if you like its sound). But look to compression first if you find your mixes lack depth—it often is the culprit.

5. Always Balance Your Instruments at the Beginning of the Mix Process
This isn’t just good mixing hygiene. It also helps carve the necessary space for creating width and depth. After listening to the multitrack session (and the rough mix, if the client sent it), set the levels and pan your tracks before doing anything else. You’ll have a much easier time carving space going forward.

6. LCR ITB: WORKED FOR ME!
ITB stands for “in the box”—i.e., not using analog processors on the signal. LCR stands for left/center/right, as these locations constitute the only places to pan your signals when abiding by this principle. More specifically, you’re aiming for hard left, dead center, and hard right.

A personal note: I had a hard time getting my mix to feel as wide as I wanted when working entirely ITB. Then I started (loosely) adhering to this panning principle (loosely, in that a stereophonic instrument, like a drum kit, stays panned to evoke its natural spread). The difference, for me, was night and day. My mixes, quite literally, opened up.

7. EQ Your Spatial Effects
You should often EQ your time-based effects to fit into the mix, because you don’t want them competing for the same frequencies as your sound sources; a muddy interplay between instruments and reverbs can cloud the depth and smear the image. This doesn’t mean, however, that an undesirable verb or delay will be improved by EQ. Always seek the best tool for the job and then improve upon it with the equalizer.

If you’re new to the game, use something like FabFilter Pro Q 2, which provides analyzers and sidechain inputs. Routing the dry track’s signal into the sidechain, you can see where the frequencies are rubbing up against each other, and compensate on the reverb/delay’s EQ to let the sound source shine through.

8. Put Your Spatial FX on AUX tracks
In addition to saving CPU by not putting reverb on every track—and creating a congruent spatial field by using two or three verbs/echoes instead of twenty—you’ll have greater control over the effect, in terms of level, panning position, and EQ. This will be of the utmost use for setting up spatial relationships, as the mixing process here is a game of degrees: too much effect and you’re swimming, too little and you’re flat, dry, and boring.

9. However...
There are situations in which you’d want to put a reverb directly onto a track, or more commonly, onto a group of tracks bussed together. Toms, for instance, often cry out for track-specific processing, as the particularly reverberant sound of the tom is both something we’ve come to expect, and something often inadequately captured in the recording process.

Try this: take a group of instruments bussed together, instantiate a reverb on their auxiliary channel, turn down the late reflections on the reverb by 15 to 30 dB or so, keep the early reflections high, adjust the Pre-delay and other parameters to taste, and edge the reverb/dry mix down to 10% or less. Now, while listening to the track, switch the reverb on and off. Do you like the depth created with the processor on? Then keep it.

10. Delays in the Nick of Time
Delays timed to the music will fold back into the mix, and furthermore, will create a naturalistic sense of depth. Example: try a stereo delay on overheads with one echo set to 1/16 notes and the other set to 1/8 notes (stock plug-in delays are perfect for this, as they are usually colorless). Keep the feedback relatively low. Sink the delay down into the mix until it's almost unnoticeable. Now, while listening to the track, switch the send on and off. You won’t hear much when it’s there, but when it’s gone, you’ll miss the sense of depth.

11. Slap Delays
One usually equates short, often-unrepeated delays (commonly called slap-back echoes) to the sound of an Elvis Presley vocal, but when used with a mono signal, these delays can impart a sense of depth—provided they are properly situated in the mix. If you pan the delay to oppose the mono signal, you can also create a sense of width. Likewise, a stereo source with a mono slap can often feel deeper, as it has a center in the background holding it together.

12. Keep Your Middle Clear
We lose a sense of depth when a reverb competes for the center panning position alongside the snare, lead vocals, bass, kick, etc. There are many tricks to mitigate this effect. Here are two:

• Send a source to two different reverbs on two different aux tracks, pan them hard left and hard right, and edge them into the mix. Your middle will clear out, and everything will tend to sit more nicely.

• Alternativeley, send the source to an aux track with reverb on it, blend a stereo delay into the reverb (timing the delay as described above), and add a modulation effect—one with a mix control so you can dial in only a smidgeon. Waves Enigma is excellent for this, because it can mimic the effect of random distribution throughout a room.

Miscellaneous Tips and Tricks

13. Stereo-izing a Mono Track
It’s not unheard of to take a mono track—a synth melody, for example—and convert it into something with a stereo spread. There are several ways of doing this. A couple have been covered in the B&H Explora article Fake it till You Make it: Turn One Guitar Track into Several. Though that piece was centered on guitar, you can use those tricks with any almost mono sound you’d wish to stereo-ize.

You can also apply a stereo EQ to the signal with M/S capabilities and achieve interesting, phase-y spatial results by equalizing the center and the sides differently.

However, please note that these methods can introduce problems. A stereo-ized delay (as covered in the cited article) might not play nice when folded down into mono playback. Likewise, a signal radically EQed in M/S mode can be so disorienting that it can cause nausea. You must be judicious.

14. Using Phase to Your Advantage
Stereo signals that are out of phase can often feel wider. However, they can mess up your mix in short order, so be careful. You can use a plug-in like Waves InPhase to manipulate stereo signals, pushing the left back a few milliseconds and the right forward a few milliseconds. On an amplified guitar, this can create some cool spatial effects.

Here’s a simple phase-widening trick, and it only requires stock plug-ins: set up a stereo auxiliary track. Flip the polarity of the left and right channels of this track, and then flip its stereo image, so that hard-right comes out on the left channel, and vice versa. Now you’ve got a tool that uses phase relationships to increase width.

Do you want a piano sound to feel wider? Buss out some signal to this auxiliary track on a send. Play with the level to taste. But you must not overdo it here, or else you’ll smear the image, rendering it imprecise and undiscernible.

15. Widen the Stereo Track with Hardware (ONLY A LITTLE!)
Many engineers like to run their mixes through high-end preamps and record the resulting stereo track, monitoring their mix-decisions off this input path. I do this myself because I love the sound it imbues. If you operate in this way, here’s a cool trick to give your overall mix a little extra width:

Usually you’d feed a preamp with signal from the left and right channels. But you don’t have to—you can set up a mid/side matrix instead, where one channel carries the sum channel (effectively, the middle), and the other handles the difference (effectively, the sides).

It’s a bit complicated to explain, and the routing takes a while to relate (ask me and I’ll do so in the Comments section), but when it’s set up, you can use the output knob of your preamp to control the level of the mid and side channels independently, instead of the left and right.

Cranking the side channel ever so slightly will increase the width in a way that, I find, surpasses the digital implementation of this effect. However, be sensible—a little goes a long way. Also, bow to your mastering engineers: if they prefer to handle the stereo width on their end, and you trust them, leave it to them.

16. Make Nice with the Correlator
How do we know we’re using too much widening? Our ears, of course, but there are visual indicators: Many plug-in meters have correlators that help you measure the degree of your stereo field and the polarity of your signal. We’ll leave off the technicalities for now, but here’s what you can concretely do: slap the correlator on your stereo output and check it out every once and a while. If the reading is between 0.5 and 1, you’re probably in good shape (again, your ears must be the final judge). If they’re going below that, you’re in trouble.

The Takeaway

You don’t need boutique plug-ins and outboard gear to get the width you want. Likewise, you don’t need tons of reverb and delay to get the depth you crave. What you need are good, clean signals, properly placed, balanced, and effected smartly. Level and panning, as we discussed above, go a long way. Then think EQ. After that, you can begin thinking about time-based effects, and all the tricks listed above. Be sure to experiment! That’s part of the joy of mixing. Just make sure that you’re able to judge the failed experimentations from the successful ones.

If you have more ideas for achieving width and depth in a stereo mix—or you want me to explain something further—please feel free to leave us a note in the Comments section, below.