Video Production

Scene Sound Design – Audio Mixing Techniques for Realistic, Immersive Sonic Worlds

Follow along with our free sound packs as we create a realistic sonic journey by selecting sounds and employing essential audio editing techniques.

Getting the right sound behind a video can make or break the realism for any viewer. It’s easy to choose the right mixture of sounds, but stringing them all together into a coherent whole requires a few technical skills… as well as a good knowledge of how your scene would sound in the real world.

In this tutorial, we’re going to construct a sonic journey from many SFX elements from both the Free SFX Cellar - Background Ambiences Pack and from our main SFX Cellar platform itself. In the scene, the listener is moving from a busy subway station, out into the city and away into a quieter area, as things happen around them all the while.

You can download our Background Ambiences Pack to construct your own scene right here…

Starting with a Crowded Ambience Sample

We’ll begin our sound scene with this file from the free Background Ambiences Pack. This is the soundscape of a busy metro station with crowd sounds, announcements and music happening in the background.

We’ll fade the start of the file in – purely as an intro to the resulting audio file. For submission, we might usually let the editor of the final project create a fade of their choosing themselves.

Metro Ambience Fade In

Adding Footsteps and Slowing Them Down

To add the sound of walking through the scene, as if the listener is walking through it themselves, we’ll add some gentle footsteps taken on a hard surface. (This has been taken from the main SFX Cellar platform rather than the Background Sounds Pack) 

The original sound is quite quick, so we’ll use the DAW’s timestretching capability to slow the sound down, without changing its pitch.

If you want to learn more about speeding up, slowing down and tuning audio, you’ll find an in-depth guide in our SFX Pitch and Timing Guide.

The audio below plays the original file in the first five seconds, and then moves onto the slowed version.

Footsteps Timestretch

Duplicating and Reducing the Footsteps in Volume

Next, we duplicate this longer footsteps audio clip to repeat throughout our ambience clip. The sound file is designed to loop without problems, so we ensure there’s no space between each clip.

When we play the whole project back, the footsteps seem inappropriately loud next to the ambience, so we reduce the level of all clips together until they sound right (selected all at once using shift). You could also use that track’s fader in the mixer.

Footsteps Duplicate Attenuate

Adding a New Background Sound and Transitioning

In our scene, we want the listener to emerge from the busy underground station into the city streets. Our next sound bed will be the Busy City Ambience file from the Background Ambiences Pack, recorded on a n urban street. Here’s how the two sounds go one after the other…

 Transition and Crossfade Pre

…of course, this would be a jarring transition that you wouldn’t expect in real life. To make this more realistic, we can crossfade the two background audio clips together over a few seconds.

Extending the Transition and Getting it Right

Actually, using a crossfade of just a few seconds doesn’t feel quite as lifelike to our ears. It’s clear we’ll need a slower, more seamless, lifelike transition between these two sounds. If you’re adding background sounds to existing video footage, you’ll have a visual cue for when one sound starts to die away and another starts to appear, but when we’re doing this ‘blind’, we have to do what feels right. 

In the real world, you’d expect the busy sounds of the metro station to die away more slowly as the hustle and bustle of the street comes in and eventually takes over. For a more cinematic experience, we might create a quicker, more jarring transition between two background ambiences to emphasize the change. In this example, we’ll make things as lifelike as possible…

We extend the crossfade region to be far longer – up to about 15 seconds – and listen back. It’s more realistic, but we can also change the crossover curve between the two, as we do below with the exponential curve. It sounds more realistic to our ears.

Longer Crossfade and Expo

Adding a Second Environment Transition

To mimic our action moving into yet another, more peaceful environment, more isolated from the city, we add in the file Air Tone with Distant Traffic and Birds from the free Background Ambiences Pack.

Here we go for a very long fade of about 70 seconds. In the real world, walking from a busy, loud environment to a nice quiet one won’t be quick. Elements of the new enviornment such as birds might be heard quite soon, while it’ll still take a while for the old, loud background noise to die down behind us. We go for a logarithmic fade to make this happen in the DAW.

Second Transition Very Long Fade

Cycling the New Ambience

We haven’t got much space left for the new ambience to take hold after that huge fade, so we’ll have to use the same file again a second time as a loop. Luckily, nobody has heard the start of the ambience very well as it was fading in.

To cycle the same audio clip, we copy it and remove all fades. The clip ends and starts with built-in fades, which we trim off. We can then crossfade the original clip’s end with the copy’s start. To keep things even and make it less noticeable, we do this with a linear fade over about seven seconds. As one dies away and the other is introduced, it’s hard to tell that anything has changed with our audio clips.

Cycle Park Ambience

Adding some Construction Sounds

We have our background ambience, our footsteps, and now it’s time to add some more sounds on top. Starting from a couple of sounds at once was relatively easy, but the more we add now, the more likely we are to break the realism.

We’ll start by adding some construction sounds into the ‘noisy’ area of our virtual walk. The Metal Grinder sounds from SFX cellar work well here.

The file is one long, constant metal grinder sound, so we’ll split it up into smaller pieces, fading each one in and out. The first ones fades in longer, right alongside the main transition between the two sonic environments.

Construction SFX

Mixing Construction Sounds into the Background

The metal grinder sound is still far too loud. We’ll turn each audio clip down, but we’ll do it differently for each. We’ll take the first and third down even lower than the second, signifying that the listener is moving towards the sound and then moving away from it after.

Now lower down in the mix, the construction sound blends in with the background, and also changes as the scene progresses to make it seem like things are moving forward in our scene.

 Construction Mix

Adding Church Bells with Panning and Automation

Next to add some church bell sounds (again from SFX Cellar) to the transition between the city and the park. We’ll start by fading them in and out as we did with the construction sounds. We’ll pan those sounds towards the left of the scene to begin with, fitting them in on one side of the listener.

But we can go further to make this scene more immersive. We’ll keep the church bells halfway to the left as we come towards them, then move them fully left as we pass them, and then back away from the left ear as we walk away. To get all this right in the DAW, we can use automation of the pan control.

Church Bells Panning

Placing Sounds in the Distance

We’ll add some more sounds to our sonic experience while walking through the virtual park. It’s easy to add some bird sounds into the background, but how about retaining some of those construction sounds – only further away in the distance now. 

This is going to need a little more technical know-how. We can portray these sounds as further away in the distance by reducing their volume, but these drills sounds still appear very present. 

Distance Effects NO

To make this part of our scene more realistic, we turn to some effects. A far-away sound will have some reverb combined with it – as the original sound bounces off buildings nearby, and the total, combined sound makes its way to us.

When sounds travel a long distance, there’ll also be some loss of certain audio frequencies – the high frequencies are absorbed by the air, and the lower ones lose some of their power. We can emulate this with an EQ that removes both low and high frequencies from the sound.

Distance Effects YES

Final Scene

And that caps off our scene – a virtual sonic walk from a subway station, through a busy city environment, and into a quiet park, made as realistic as possible.

Final Scene

Remember, you can download all the background sounds used in this tutorial as part of the free Background Ambiences Pack, which you can download right here in the box below. In the pack you’ll find fireworks, room tone, animals, interiors and more giving you the palette to design the perfect soundscape for your scene.

April 30, 2020