procedural game audio Asbjoern Andersen


How do you keep your game audio varied – without needing countless individual audio files? Procedural sound design can help with exactly that, and in this hands-on guide, senior lecturer, teacher fellow and author of the Game Audio Implementation book, Richard Stevens, demonstrates how the concept works in the Unreal Engine.

When creating a sound effect for a movie you’ll know that the audience is only going to hear it on one specific occasion, and you’ll likely build it up through editing and layering different sound elements to get just what you want.

01_game_audio_Explosion

Figure 01 ‘An explosion’

 

Most games, like sports, are about skill and mastery, so the player will be repeating similar actions again and again, and consequently they will be hearing the same sounds again and again. The trouble is that we’re very sensitive to this kind of repetition, since it just doesn’t happen in real life.
 



Explosion_Baked


Video: Explosion Baked


 
The obvious answer is just to have loads and loads of sounds but it would be far too much work to create 30-40 versions of every sound in the game (plus there are obviously limitations as to how much we can fit on a disk!).
If we look at our ‘explosion’ sound again we can see that the final sound is made up of different characteristic components, and this idea is key to starting to think about procedural approaches to sound design.

02_game_audio_Explosion_Components

Figure 02 ‘Explosion Components’

What we want to do is to keep these components separate when we import them into a game so that we can recombine them in different ways at run time. A lot of sounds in games aren’t ‘sounds’ at all, they are systems of sounds. This kind of procedural approach requires a different way of thinking, and sometimes different kinds of sound assets, since we often want to isolate the individual components that make up a sound.

When we bring these components into a Sound Cue in the Unreal Engine we can build a system of playback, and by having a few different versions of each component we can randomly combine them to create variation.

03_game_audio_Procedural_Explosion

Figure 03 ‘Procedural Explosion’

 



Explosion_Components


Video: Explosion Components


 
By taking this approach we don’t need thousands of complete sounds in our game to be able to get thousands of different sounds out of the system. Randomizing the combinations of layers can vastly increase the number of potential outcomes with only a few additional sounds.

By taking this approach we don’t need thousands of complete sounds in our game to be able to get thousands of different sounds out of the system

In the above example we have four sets of three possible sounds that can potentially be heard so this will give us 81different sound outcomes. If we added just one other ‘Crack’ element then we’d get 108 potential sounds.


WANT MORE LIKE THIS?
FOLLOW A SOUND EFFECT FOR THE LATEST IN FANTASTIC SOUND:
 
          

We can increase this variation even more by adding some slight randomized delays and modulations of pitch and volume to each element, giving us.. erm… a very large number of possible outputs.

04_game_audio_Delay_Mod

Figure 04 ‘Adding Delay and Modulation nodes’

[tweet_box]Why Procedural Game Sound Design is so useful – demonstrated in the Unreal Engine:[/tweet_box]



Explosion_Delays_and_Modulations


Video: Explosion Delays and Modulation


 

Another thing we might want to do is to change the sound depending on what was being blown up, or the materials of nearby objects. Again by keeping these material components separate we can choose to layer them into the Sound Cue when appropriate by using a switch.


Popular on A Sound Effect right now - article continues below:


Trending right now:

  • ⏰ For a very limited time:
    Add this library to the cart and enter ah4launch in the cart coupon field – to sprinkle an extra launch discount, on top of the current discount!

    Animal Hyperrealism Vol IV is a sound library containing animal vocalisations, from real to designed creatures totaling more than 2000 individual sounds in 294 files. The sounds were recorded in zoos, and wildlife centers.

    The asset list includes but is not limited to: hippos, hyenas, vultures, dwarf mongooses, elephants, African cranes, parrots, tigers, pigmy hippos, rhea ostriches, brown bears, pheasants, wildebeests, African wild dogs and many more. The content has been recorded at 192KHz with a Sanken CO100K, an Avisoft CMPA and a Sennheiser 8050 for center plus two Sennheiser MKH8040 for stereo image.

    The resulting ultrasonic spectrum is rich and allows for truly extreme manipulation of the content.

    15 %
    OFF
  • FOUR ELEMENTS - Rock The Speakerbox Professional SFX

    Master the Art of Bending the Elemental Forces

     

    Unleash the raw power of fire, water, earth, and air with this comprehensive 9 GB sound library featuring 3050 high-quality sound effects across 630 files. Whether you’re designing cinematic soundscapes or enhancing video games Four Elements delivers the tools you need to harness the energy of the natural world.

    Construction Kit – 2443 Sounds

    A treasure trove of raw, organic, and processed sounds including seamless loops divided into Fire, Water, Air, Earth and Explosion categories. Customize every detail with an extensive selection of sound components.

    • Organic Fire: Campfire sizzles, torch whooshes, and flame bursts.
    • Processed Fire: Distorted impacts and unique crackles.
    • Organic Earth: Rock crashes, gravel scrapes, and heavy stone hits.
    • Processed Earth: Stylized rumbles and granular textures.
    • Organic Water: Ocean waves, hydrophone bubbles, and fluid splashes.
    • Processed Water: Underwater whooshes and stylized liquid smashes.
    • Organic Air: Bamboo swishes, cloth movements, and pressure bursts.
    • Processed Air: Filtered gusts and dynamic noise sweeps.
    • Explosion: Firework detonations, Butane bursts, and cinematic impacts.

    Building Blocks – 416 Sounds

    Game-ready sound layers featuring Impacts, Whooshes, and Textures as seamless loops. Elevate transitions and enhance atmospheres with loops and pre-designed sound layers.

    • Fire: Explosive bursts, blazing infernos, and warm embers.
    • Earth: Ground-shaking impacts, crumbling terrain, and heavy collisions.
    • Water: Cascading waves, serene rivers, and underwater ambiences.
    • Air: Whispering breezes, stormy turbulence, and slicing gusts.

    Design Kit – 192 Sounds

    A collection of ready-to-use sound effects divided into Attack, Bend, and Explosion categories for quick integration into your projects. Perfect for high-energy scenes and immersive storytelling.

    • Fire: Crackling flames, fiery bursts, and roaring infernos.
    • Earth: Crushing impacts, shifting ground, and massive land eruptions.
    • Water: Splashes, fluid manipulations, and crashing tidal waves.
    • Air: Slicing winds, swirling currents, and thunderous gusts.

     

    Four Elements gives you complete creative control, blending organic recordings with processed sound layers to meet the demands of any project. Master the forces of nature with Four Elements. Let your creativity ignite.

     

    Keywords:

    Elements, Fire, Water, Earth, Air, Wave, Water, Liquid, Rock, Cast, Stone, Pebble, Torch, Gas, Flame, Campfire, Sizzle, Burst, Scrape, Whoosh, Impact, Texture, Attack, Bend, Bending, Explosion, Processed, Surge, Quake, Hit, Flow, Burn, Ignite, Drop, Smack, Destruction, Rumble, Hiss, Blow, Wind, Cloth, Movement, Underwater, Bubble, Ocean, River, Lake, Firework, Firecracker, Bang, Blast, Detonation, Magic, Fantasy, Forces, Fire Magic, Water Magic, Earth Magic, Fire Air, Fire Effect, Fire Whoosh, Water Whoosh, Seamless Loop, Loop, Fire Cast, Water Cast, Earth Cast, Air Cast

  • Bundles Audiohero – The Prodigy Play Track 300000 sounds included $5

    Download 50 Sound Effects for $9.99 within a month from a library of more than 300,000 tracks. We give you Access to a wide variety of collections from Sound Ideas and the Hollywood Edge, including categories such as ambiance, animals, comedy, cartoon, crashes, designed sounds, foley, feature film, guns, sci-fi, production elements, sports, surround sound, transportation, and the list goes on! Instead of purchasing a boutique library, choose from an extensive library ala carte. We provide you with the massive audio library without the large cost.

    The sound effects are all recorded in 24bit 96khz down to 16bit 44.1khz. These sound effects have been used in many productions such as feature films, video games and all types of broadcast.

    What you get:

    Purchasing this offer gets you a special code that lets you download 50 sound effects from Audiohero.com within a month. The sounds you get with this purchase are covered under the Audiohero EULA.

    50 %
    OFF
    Ends 1767135600
  • Spell Variations – Complete Collection is the magic sound bundle, combining all 4 spell sound libraries into one package. Inside, you’ll discover an extensive range of spells, elemental forces, dark incantations, arcane rituals, healing charms, summonings, enchanting whooshes, and much more, delivering a complete arsenal of magical sound effects for any creative project.

    This collection features 1,268 premium-quality sound effects, meticulously organized into 143 unique spell types, each with multiple variations to ensure no spell ever sounds the same, even when reused.

    Every spell type is carefully named and organized into dedicated folders, giving you intuitive navigation and maximum flexibility for magical scenes, game mechanics, cinematic transitions, or immersive soundscapes.

    Recorded, edited, and mastered at 192 kHz / 24-bit, these sounds provide exceptional clarity and full adaptability for pitching, layering, and creative sound design.
    An essential library for professional sound designers looking for ready-to-use magical sounds for video games, trailers, animations, or any high-end audiovisual production.

    More about the pack
    – Intuitive file naming
    – All you’ll ever need regarding magical sounds [Use them again & again
    – Use the sound effects over and over, in any of your projects or productions, forever without any additional fees or royalties. Use the SFX in your game, in your trailer, in a Kickstarter campaign, wherever you need to, as much as you want to.
    – Totally mono compatibility
    – All sounds have several variations.
    – Use your imagination and feel free to use any sound for a creature other than the one described, remember that the world of sound is totally subjective.


Latest releases:

  • Hand Combat Sound Effects Violent Combat Play Track 4213 sounds included From: $135 From: $108

    THE RAW SOUND OF CINEMATIC FIGHTING

    VIOLENT COMBAT is a professional sound effects library built for fight scenes that demand impact. Packed with punch sound effects, fight sound effects, and powerful combat sound effects, it delivers everything from raw realism to over-the-top cinematic action. With improved fidelity and greater variation than its predecessor CLOSE COMBAT, this collection gives sound designers production-ready audio for film, TV, and games.

    Violent Combat | Sound Effects | Trailer

    From Realism to Cinematic Exaggeration

    Dial in the tone you need with dedicated categories: Martial Arts, Grounded, Over The Top, and Gory. Whether it’s kung fu sound effects, karate sounds, or exaggerated wrestling hits, you can shift seamlessly from authentic to stylised.

    Successor to Close Combat

    VIOLENT COMBAT builds on the legacy of CLOSE COMBAT with higher fidelity recordings, better-organised categories, and more variation. It’s the ideal companion, giving you the flexibility to cover every style of fight scene.

     

    Sounds That Land With Force

    Recorded with a wide range of props and techniques, each fighting sound effect has real weight. Where needed, selective pre-processing boosts impact, avoiding the flat results of real fight recordings.

    Production-Ready and Versatile

    Equally at home in film, TV drama, high-end game audio, or immersive theatre. From knockout sound effects to stylised fight sequences, Violent Combat is ready to drop straight into your mix.


    Included Sounds – KEYWORDS

    AIR, BODYFALL, CLOTH, CRUNCH, FINISHER, FURNITURE, GORE, GRAB, GRAPPLE, IMPACT, KICK, LEATHER, MARTIAL ARTS, METAL, MOVEMENT, PLASTIC, PUNCH, SLAP, SWISH, SWOOSH, THROW, WHOOSH

    20 %
    OFF
    20 %
    OFF
    20 %
    OFF
    20 %
    OFF
  • ⏰ For a very limited time:
    Add this library to the cart and enter ah4launch in the cart coupon field – to sprinkle an extra launch discount, on top of the current discount!

    Animal Hyperrealism Vol IV is a sound library containing animal vocalisations, from real to designed creatures totaling more than 2000 individual sounds in 294 files. The sounds were recorded in zoos, and wildlife centers.

    The asset list includes but is not limited to: hippos, hyenas, vultures, dwarf mongooses, elephants, African cranes, parrots, tigers, pigmy hippos, rhea ostriches, brown bears, pheasants, wildebeests, African wild dogs and many more. The content has been recorded at 192KHz with a Sanken CO100K, an Avisoft CMPA and a Sennheiser 8050 for center plus two Sennheiser MKH8040 for stereo image.

    The resulting ultrasonic spectrum is rich and allows for truly extreme manipulation of the content.

    15 %
    OFF
  • Weather Sound Effects Hyper Thunder Play Track 800+ sounds included $49.50

    Hyper Thunder is a colossal collection of thunder and lightning, 100% crafted from the ground up using innovative synthesized technics and props recordings. Not a single real life thunder recording was used. using synthesis and props manipulation crafted to deliver impact far beyond natural recordings. Built entirely from innovative synthesis and props recordings, this library pushes the boundaries of weather sound design—perfect for when you need the raw energy of a storm dialed up to cinematic extremes.

    Featuring over 800 files, Hyper Thunder spans everything from subtle distant rumbles and rolling thunder to razor-sharp lightning strikes and earth-shaking impacts. With both designed hits and source layers, you have full control—drop in ready-to-use power or sculpt your own stormscapes using the source recordings.

    Created in collaboration with Bruits.Studio’s Vincent Fliniaux and Tibo Csuko—longtime SoundMorph contributors to acclaimed libraries like Robotic Lifeforms 2 and WATER— Hyper Thunder blends technical mastery with bold creativity.

    Key Features

    • 800+ files of synthesized thunder and lightning
    • Both designed hits and source layers for full creative control
    • Covers subtle distant rumbles through to massive cinematic impacts
    • Crafted 100% from synthesis for a unique, larger-than-life sound
    • Perfect for film, games, trailers, and any project needing storm power
    • Created in collaboration with Bruits.Studio’s Vincent Fliniaux and Tibo Csuko (Robotic Lifeforms 2, WATER)

    From atmospheric detail to explosive drama, Hyper Thunder gives you thunder and lightning that are bigger, subtler, and more versatile than nature itself.

    50 %
    OFF
  • 638 meticulously processed stereo fire spells sound effects recorded in 96 khz and 24 bits for high audio definition.

    The collection comes with hundreds of variations, more than 1 hour of content and many different type of fire spells. It also includes source sounds for more flexibility for your projects.

    This collection is perfect for any films, video games or trailers.

    The library is fully focused on fire spells. You will find simple one shot magic firebolt, powerful high level fire spells, fire sword, berserker enchantments and so on. Spells such as fireball,  firewall, rain of fire, meteor, fire nova, magma storm, pyroblast, sword of Avernus, etc. are included in this library.

     

    THE ARCANE FIRE SPELLS
    38 %
    OFF
  • Immerse yourself in an atmosphere of natural power and tranquility with the “Rain and Thunderstorm” sound collection, consisting of 4 Vol-s.
    This collection features a variety of looped sounds: light rain, night rain with loud thunderclaps, and other effects that will help you create the perfect atmosphere – from a quiet, secluded night, long scenes, or endless atmospheric effects without abrupt transitions, to a dramatic thunderstorm on the horizon.
    The recording was made by a Zoom H3-VR recorder in the Ambisonics A format (96 kHz 24 Bit) and then converted to the AmbiX and Stereo formats (96 kHz 24 Bit), which are located in different folders of this sound pack.

Need specific sound effects? Try a search below:


By getting information from the game about what type of material is being blown up we can use this to control the switch, and therefore which material components of sound get added to the overall explosion sound.

05_game_audio_Explosion_Materials

Figure 05 ‘Explosion Materials’

Thoughts on the term ‘Procedural Sound Design’:

In writing the book we made a conscious decision to term this kind of sound design, that is typical in the current practice of game audio, ‘Procedural Sound Design’ to differentiate it from ‘Procedural Audio’.

Andy Farnell, who coined or at least popularised the term ‘Procedural Audio’ sees it as any kind of system where the sound produced is the result of a process. He describes these ideas more fully here. So under that definition, as soon as you set up any kind of system of playback you could see it as being procedural audio.

However there has been a lot of important work and progress in terms of procedural audio for games in the last few years (see http://proceduralaudionow.com/), and this has encompassed a variety of techniques, but there has been some emphasis on the idea of these procedural systems being synthesis based, which ultimately is probably the most flexible solution for interactivity.

This is a specialist field which we don’t go into in any depth in the book since there are other great books out there on this (not least Andy’s book ‘Designing Sound’). In the book we attempt to describe the range of procedural approaches by saying, “This approach to sound design exists on a spectrum from procedural sound design, where we tend to be manipulating pre-existing assets, to procedural audio, a term more frequently used when systems of synthesis are used to generate the sounds themselves (with much in between that combine both approaches)”.

To throw another thing into the discussion, when discussing music systems we also use the term algorithmic, which again could be used to describe any kind of system of playback. Although we could just call this procedural music (as others such as Karen Collins have done), but we felt it worth preserving and highlighting ‘algorithmic’ given the long history of algorithmic techniques explored for music in the past, which a search for ‘procedural music’ is going to miss.

 



Explosion_Materials


Video: Explosion Materials


 

Now we have all the elements of a sound as separate components we can also do other things with them, like spatialize them around the player in different ways. For the Game Audio Implementation book we built a simple system that will throw sounds around the player for people listening in 5.1 or 7.1. This could be used for elements of the explosion itself or for debris.

06_game_audio_Spatialized_Diagram

Figure 06 Diagram

 

07_game_audio_Spatialized_Detail

Figure 07 Detail

 

This was done in Unreal’s Blueprint system – which looks a bit daunting at first but once you get the hang of it you can pretty much do anything you might dream up!

08_game_audio_Blueprint

Figure 08 Blueprint

 



Explosion Spatialized


Video: Explosion Spatialized


 
By using a procedural approach to sound design we now have an explosion sound that’s different each time, is ‘aware’ of the different materials involved in the explosion, and spatializes around the player in stereo, 5.1 or 7.1.
 

A big thanks to Richard Stevens for his insights on procedural game audio! If you want to know more about procedural sound design for games then check out the Game Audio Implementation book from Focal Press. If you’re new to UE4 you can get UE4 here for free, and you can download all the levels that go alongside the book here (also for free!) to get started.
 

Please share this:


 



 
 
THE WORLD’S EASIEST WAY TO GET INDEPENDENT SOUND EFFECTS:
 
A Sound Effect gives you easy access to an absolutely huge sound effects catalog
from a myriad of independent sound creators, all covered by one license agreement
- a few highlights:
  • ⏰ For a very limited time:
    Add this library to the cart and enter ah4launch in the cart coupon field – to sprinkle an extra launch discount, on top of the current discount!

    Animal Hyperrealism Vol IV is a sound library containing animal vocalisations, from real to designed creatures totaling more than 2000 individual sounds in 294 files. The sounds were recorded in zoos, and wildlife centers.

    The asset list includes but is not limited to: hippos, hyenas, vultures, dwarf mongooses, elephants, African cranes, parrots, tigers, pigmy hippos, rhea ostriches, brown bears, pheasants, wildebeests, African wild dogs and many more. The content has been recorded at 192KHz with a Sanken CO100K, an Avisoft CMPA and a Sennheiser 8050 for center plus two Sennheiser MKH8040 for stereo image.

    The resulting ultrasonic spectrum is rich and allows for truly extreme manipulation of the content.

    15 %
    OFF
  • Foley Sound Effects Footsteps Bundle Play Track 3800+ sounds included $36

    The ‘Footsteps Bundle’ combines ‘Footsteps One‘ and ‘Footsteps Two‘ libraries together and brings you over 3800+ high quality footstep sounds on 19 unique surfaces to enrich the audio of your next project.

    Surfaces included:

    Dirt • Dry Sand • Dry Swamp • Forest Plain • Forest Plain II • Frozen Stairs • Grass • Grass Long • Grass Short • Gravel • Pine Needle Ground • Snow Deep • Snow Packed • Snow Scrape • Water Deep • Water Shallow • Wet Swamp • Wood Scrap • Wooden Stairs


    You get the sounds in two formats: 96 KHz 24 bit and in 44.1 KHz 16 bit, for more convenient ways of utilizing the sounds in games and other media.

    20 %
    OFF
  • Metal Sweeteners / Gun Hyper-Realism contains hundreds of metal sounds to enhance your gun fights.

    We recorded tons of different metallic objects like wrenches, cameras, stands, microphones,etc… to create different hits and textures for the Source Material kit, everything was recorded at 192 kHz with the famous Sennheiser MKH 8040/8050 microphones in order to capture all the harmonics up to 50-60 kHz.  Then we layered/edited/pitched, crushed them to create the sounds in the Designed folder.

    The “Source” folder contains 91 files and hundreds individual sounds divided into these categories:
    – Hit
    – Scrape
    – Screw
    – Rattle
    – Mech
    – Click
    – Slide


    The “Designed” folder contains 20 files and many more individual sounds, all created from the “Source Material”:
    – Silenced/Suppressed shots
    – Reload
    – Bullets
    – Mechanics
    – Ejections

    The “Synced” folder contains multiple groups of 8 layers + 3 silencers/suppressor, all sync’ed on some of the most common guns rate of fire :
    – Ak 47
    – M16
    – Uzi
    – MP5
    – M60
    – M4

    All the sounds are 192 kHz / 24 bits, giving you all the process flexibility you need. Most importantly the files are embedded with exhaustive metadata compatible with Soundminer, Basehead, etc…

    This library is perfect to spice up “boring” real life recordings, create a whole new futuristic weapon or just to give that ” Hyper Realistic ” feel to the project you’re working on.

Explore the full, unique collection here
 
 
   

3 thoughts on “Why Procedural Game Sound Design is so useful – demonstrated in the Unreal Engine

Leave a Reply

Your email address will not be published. Required fields are marked *

HTML tags are not allowed.