Mixing: Depth & How To Increase Mix Depth

Creating a sense of dimensionality is critical when mixing. Depth is one of the most important dimensions to get right in the mix. Even in mono mixes, which by definition have no width, the dimension of depth is key, and even more so because of the lack of width.

In this article, we'll discuss the depth dimension in greater detail and consider a few strategies for enhancing this dimension in our mixes.

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What Is Depth In A Mix?

Mix depth refers to the perceived distance between the listener and the sound source (track) in a mix. The depth of the mix as a whole is largely dependent on the variety of depths between different sound sources (and effects) and notably between the closest perceived element and the furthest perceived element.

In the real world, we can approximate the distance between our location and the location of the sound source intuitively.

When mixing, we should keep this real-world dimensionality in mind in order to produce realistic and sonically pleasing results.

I should harp on the fact that perceived depth, like all dimensions, requires contrast. We can't have anything sound close if nothing else sounds far, and vice versa. Fortunately, the time-based effect we use to mimic spatial acoustics in the mix provides such contrast by default (against the dry signal being processed by such effects). However, I felt it necessary to add that important note before we get to our depth-creating strategies.

As we'll discuss, getting a strong sense of depth in the mix is made possible with time-based/spatial effects (delay and reverb) and by altering levels, high-end frequency content, and transients.

I have a video going into my top 11 strategies for creating depth in a mix. You can check it out below:

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Enhance Mix Depth With Contrasting Levels And Effects

As was mentioned earlier, dimensionality (including depth) is all about contrast. The mix elements perceived in close proximity must be juxtaposed with distant-sounding elements in order for depth to truly be established.

The primary tool we have for adjusting the relative depth of tracks within the mix is the simple fader. Yes, altering the relative levels of tracks is the easiest way to create a sense of depth within the mix. The simple truth is that, all else being equal, louder elements sound closer than quieter elements.

Therefore, contrasting levels are an easy way to create a sense of depth in a mix.

In addition to levels, we can also provide contrasting depth-inducing effects such as delay and reverb (which we'll get to shortly).

For starters, we can send varying levels from each track to a common delay or reverb effects return channel. That way, the delay or reverb will process more or less of certain tracks. For example, a quieter track with more signal being sent/processed by a delay or reverb return will sound even more distant compared to a louder track with less signal being sent/processed by the same delay or reverb return.

For example, we can send a guitar and vocal to the same delay return but send less of the vocal. Therefore, the vocal will be less affected by the delay, allowing it to sound a bit closer than the guitar while both instruments still sound “glued” together.

Next, we can actually utilize different delay/reverb parameters or even different delay/reverb units on different tracks to evoke more differentiation in perceived depth/distance. Utilizing different time-based effects can lead to a greater sense of depth, so long as we avoid the potential uncanniness that arises from too much variety.

For example, we can use a “larger” reverb on drums to push them further back and a “smaller” reverb on the vocals to keep them upfront.

But perhaps I'm getting ahead of myself. Let's move on to the specifics of delay and reverb as effects and the inherent contrast they create in the mix, particularly when it comes to the depth dimension.

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Enhance Mix Depth With Automation

With the importance of contrast in our minds, let's talk about automation.

One surefire way to enhance the depth throughout the mix is to automate the depth between different sections.

The most common example of this is to automate the depth of the mix so that the choruses sound deeper and larger than the previous sections.

If we can make certain sections sound deeper than others, we can make the depth of the mix more dynamic and enhance the overall dimensionality experienced by the end listener. This can be done abruptly with sudden automation moves (or arrangement), or gradually with smoother automation drawn out over time.

Consider adding automation to any of the strategies listed in this article. Remember that music is about changing sound over time, and automation is one of our primary tools for achieving change in the mix over time.

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Enhance Mix Depth With Reverb

Reverb is an effect that generally aims to recreate the natural result of reverberation, which happens when a sound wave hits a surface (or multiple surfaces) and reflects back to the listener at varying times and amplitudes.

Though there are different types of reverb and many parameters to be aware of, the effect is typically used to create a complex echo that produces information that emulates dimensional space within the mix.

After simple level balancing, reverb is the most important tool we have for creating a sense of depth.

While this isn't a masterclass on reverb, we can go over the basics here.

Sound naturally travels in acoustic environments, from the sound source through the medium/media (we're most familiar with air). As sound waves reach a boundary (a changing of the medium, most typically a physical surface), some of the sound wave energy is absorbed, some is reflected, and some is transmitted into and through the new medium.

The listener will hear some amount of the direct sound (directly from the source) and some amount of reflections (not only the initial reflections but also the second, third, fourth, and so on, as the sound waves bounce around the acoustic environment).

The sound of such reflections is processed automatically by our auditory system, giving us a sense of the acoustic space we find ourselves in.

If sound sources are close, we'll hear more direct sound, fewer initial reflections, and perhaps even fewer additional reverberant reflections. As we move further from a sound source, the ratio of direct sound to the reflected sound we hear decreases. If the acoustic space is large enough, reflective enough and if we can distance ourselves far enough from the sound source, we may very well hear more of the reflections than the direct sound.

Reverb effects, whether spring, plate, algorithmic or convolution, aim to recreate this natural effect (though they certainly can produce unnatural effects as well). That's why we'll often find parameters such as size (emulating the size of the room), initial reflections (emulating the strength of the first reflections and the overall reflectivity of the acoustic space), and decay (emulating the time it takes for the reflections to die down after the source initially produces the sound).

So if you're looking to add a sense of depth to your mix, whether you want a natural sound or a special effect, reverb is a go-to tool.

Another important parameter on reverb plugins is the wet/dry mix control. This allows us to dial in the amount of “dry” unprocessed signal and “wet” processed signal that is outputted from the reverb. This wet/dry control allows us to insert reverb effects directly on channels and not have the signal get completely drenched in the spatial effect.

Better yet, we can insert the reverb on its proper effects return channel and have its mix control 100% wet, send multiple tracks to it, and have a common reverb with much more control (independent fader control as well as additional inserts for other processing).

By having dry signals and wet, reverberant signals, we can effectively mix the “direct sound” against the “reflections” to control the contrast of the reverb effect. We can make elements sound like they're in real space within the mix by having the direct and wet signals, and we can make things sound further away by increasing the reverb amount and/or level or make things sound closer by decreasing the reverb amount and/or level (relative to the direct/dry sound).

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Enhance Mix Depth With Delay

Along with reverb, delay is the other time-based effect used to convey a sense of space and depth in the mix.

Delay, as the name would suggest, is an effect/process that delays the incoming signal and plays it back after a defined time control. Likening delay to real-world acoustics, it effectively mimics reflections within an acoustic space.

To reiterate, a sound source will produce sound waves. The sound waves will travel through the air, reaching us as listeners as well as the boundaries of the acoustic space. As sound waves reach a boundary (a changing of the medium, most typically a physical surface), some of the sound wave energy is absorbed, some is reflected, and some is transmitted into and through the new medium.

In larger acoustic spaces, these reflections are sometimes heard as distinct echoes. In smaller spaces, where the reflections reach our ears more rapidly, we may not hear distinct echoes, though the information within the reflections is interpreted by our brains in a way that tells us about the acoustic space around us.

These echoes can be emulated with delay.

Beyond the rhythmic and special effects achievable with delay effects, we can also use delay to approximate depth in our mixes.

All else being equal, longer delay times, as was mentioned, can evoke a sense of a larger, deeper space in the mix. Shorter delay times can give us a sense of a smaller space. Stereo delays are great for yielding a more natural sense of space since we naturally hear sound in stereo (we have two ears).

Any additional repeats of the signal (achieved with the repeats, feedback or regeneration controls) can also give us a sense of a larger space with more distinct second, third, etc. echoes.

I should mention that because delay only produces such echoes, it comes second to reverb in its ability to produce a sense of realistic space in the mix. That stated, the relative cleanliness of distinct echoes without the reverb tail gives delay effects an edge in denser mixes as delay reduces the risk of washout and excessive frequency and transient masking.

When it comes to the dimension of depth, delay gives us an inherent sense of contrast between the dry, unprocessed signal and the delayed version(s) of the signal. Like reverb, most delay effects will have a wet/dry mix control.

All else being equal, more dry signal will emulate a closer sound source (more direct sound). More wet signal will emulate a further sound source (more reflections compared to the direct sound).

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Enhance Mix Depth By EQing The High-End

As sound waves travel through space, they lose energy due to the friction of molecules within the medium/media. This loss of energy is experienced largely as a drop in amplitude. More specifically, sound waves follow the inverse-square rule, which states that sound intensity will drop by roughly 6 dB for every doubling of distance.

But things aren't equal across all frequencies. Indeed, it's the higher frequencies (with shorter wavelengths) that experience more attenuation per distance travelled.

What this means is that we'll naturally hear more top end from close sound sources and less top end from distant sources.

We can take advantage of this acoustic trait in our mixes. Using high-shelf filters, we can boost the high-frequencies to make a track sound closer or cut the high frequencies (or use a low-pass filter) to push a track further back in the mix.

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Enhance Mix Depth With Transient Shaping

This technique is similar to the previous one since a lot of transient information is in the harmonics of the upper midrange and high-end frequencies.

A transient is the initial burst of energy from a sound source. Take a tuned instrument as an example; the transient is made up of rich harmonic content above the fundamental frequency (the note being played) that gives the instrument its distinctive tone and timbre.

The transient harmonics of a sound have their own amplitude envelopes, where the harmonics peak quickly at varying levels and die out at varying levels.

We can hear the transient information of a sound source more clearly when we're closer to it. There are two main reasons for this:

1. The higher frequencies, which contain some of the transient harmonics, can be heard more clearly as the air hasn't yet absorbed them.
2. There is more direct sound relative to reflections and reverberation, making the initial transient less washed out and more clear.

So then, we can utilize transient shaping to enhance the perceived transients of a signal, helping bring that track forward in the depth dimension or, conversely, use transient shaping to dull the transient and move the track back in the mix.

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Enhance Mix Depth With Compression

In addition to dedicated transient shapers, we can also shape transients (and reduce dynamics) with compression.

We've already discussed transient shaping and its potential effects on perceived distance/depth. When using compression, short attack times will generally reduce transient levels, while longer attack times can sometimes give the sense of increased transient energy. Adjust the release time as necessary to achieve such an effect.

Now, when it comes to dynamic range compression (reducing the ratio between the “loudest” and “quietest” parts of a signal), compression can have an interesting effect on perceived depth. It tends to have the effect of making elements that are already mixed close sound closer (think of up front and centre, compressed lead vocals, for example) while making elements that are already mixed far sound further (think of bus compression on drums that are mixed a bit behind other elements, for example).

So with transients and dynamics in mind, we can use compression to bring things forward or move things back along the depth dimension within our mixes.

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Enhance Mix Depth With Recording Techniques

Before we ever get to mixing, we can record our sound sources in such a way that yields a sense of space and depth. Understanding the basics of acoustics and recording techniques can also help us make more sense of the previous strategies for achieving depth in this article.

Naturally, close-miking (spot-miking) a sound source will produce audio signals that, when played back, sound close. Similarly, miking sound sources at a distance will produce audio signals that, when played back, sound further away.

As I've explained previously, this has to do with acoustics and how we naturally hear sound. If we think of microphones as being “electric ears”, it all makes sense.

A microphone placed closer to a sound source will:

• Pick up more top-end since there is less distance for the sound wave to travel, and thus less high-end energy will be absorbed by the air before the sound wave reaches the microphone diaphragm.
• Pick up more direct sound relative to the initial reflections and reverberation characteristic of the acoustic space.
• Be louder (before mixing) and pick up less bleed, noise and environment noise since the mic is close to the sound source.

Conversely, a microphone placed further from a sound source will yield the opposite of the points mentioned above.

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Related Questions

What is width in a mix, and how do I increase it? Width refers to the perceived locational and directional differences of sound sources (tracks) within the mix. The stereo mix, as a whole, has a width dimension dependent on the differences between the left and right channels. The sense of width can be enhanced in the following ways:

• Contrasting panning and effects
• Reverb
• Delay
• Haas effect
• Doubling
• Stereo widening effects
• Recording techniques

What is height in a mix, and how can I increase it? Height refers to the frequency content of a track or mix. The contrast and balance of frequencies within the audible range give us the dimension of height in a mix. The sense of height can be enhanced in the following ways:

• Contrasting elements
• Arrangement
• Filling out the frequency spectrum
• Reducing frequency masking
• Automating height between sections