Audio Pro

1 - Audio Event Graph

The Audio Event Graph is a visual node-based editor for authoring complex sound events. Instead of a single clip pool, you connect sources, filters, effects, and routing nodes into a graph that evaluates as a data-flow pipeline. Each .audiograph file is one sound event. At runtime, the graph maps directly to a live audio processing chain.

For component properties and C++ extension, see the Framework API reference.

Contents

• How It Works
• Phase Lifecycle
• Nodes
• Using Variables
• Playing at Runtime
• Quick Reference
• Glossary
• See Also

How It Works

Nodes in an Audio Event Graph evaluate left to right in topological order. Connections carry AudioRoute values — handles to a point in the audio processing chain. The signal flows through:

1. An Entry node gates which phase is active
2. Source nodes create and output audio
3. Filter and effect nodes process the signal
4. Routing nodes (If/Switch) direct the signal based on variables
5. The Output node wires everything to a mixing bus

Only nodes affected by a change re-evaluate — the rest are skipped. This makes variable-driven sound modification cheap even for complex graphs.

Phase Lifecycle

Every Audio Event Graph supports up to three phases:

Phases transition automatically: Start fires once, Loop repeats while looping is enabled, Finish plays when FinishAudioGraph() is called. Not all phases are required — a simple one-shot only needs Start.

Entry nodes share routing freely. A source wired to both Start and Loop phases produces sound in both.

Nodes

Source Nodes

Both support volume, pitch, delay, looping, and 3D spatialization.

Filter Nodes

LowPass, HighPass, BandPass, Notch, PeakingEQ, LowShelf, HighShelf — all take audio_in and output audio_out. Parameters (cutoff, Q, gain) can be set per-node or bound to graph variables.

Effect Nodes

Routing Nodes

IfNode and SwitchNode route AudioRoute values based on conditions or a selector variable. Use these for conditional audio paths — different sounds based on surface type, weather, or character state.

Output Node

Aud_OutputNode wires the final signal to a named mixing bus. Every graph needs exactly one Output node.

Using Variables

Declare variables in the Variable Panel. Bind them to filter parameter slots (right-click > Convert to Reference) or use If/Switch nodes to route based on them.

At runtime, setting a variable re-evaluates only the nodes that depend on it — the rest of the graph is untouched.

Common patterns:

Variables are set from gameplay code via the Audio Manager:

SetAudioGraphVariable(instanceId, "underwater", 0.8)
SetAudioGraphVariableBool(instanceId, "isSprinting", true)

Playing at Runtime

All Audio Event Graph playback goes through the Audio Manager.

Fire-and-Forget

For one-shot sounds with no runtime modification needed:

PlayAudioGraph("Assets/Audio/Explosion.audiograph")

Manual Control

For sounds that loop, need variable updates, or need explicit stopping:

1. AcquireAudioGraph(assetPath) — get an instance ID
2. SetAudioGraphLooping(id, true) — if it loops
3. SetAudioGraphEntity(id, entityId) — for 3D tracking
4. FireAudioGraph(id) — start playback
5. SetAudioGraphVariable(id, name, value) — update variables any time
6. StopAudioGraph(id) or FinishAudioGraph(id) — stop cleanly
7. ReleaseAudioGraph(id) — return the instance to the pool

Quick Reference

Glossary

For full definitions, see the Glossary.

See Also

• Framework API: Audio Event Graph — Full node catalog and extension guide
• The Basics: Audio Manager — Runtime playback API
• The Basics: Audio Events — Simpler fire-and-forget sound playback
• The Basics: Mixing — Mixing buses that graphs route through

Get GS_Audio

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2 - Geometric Acoustics

The free gem places sounds by direction and distance — a sound behind a wall is quieter because it is further away, not because the wall is there.

Geometric acoustics makes the wall matter. Mark up your level and sounds get occluded by what is between them and the player, and pick up reverb from the room the player is actually standing in.

For settings and behaviour detail, see the Framework API reference.

Contents

• Setting It Up
• Marking Up a Level
• Choosing Materials
• Tuning Occlusion
• Tuning Reverb
• What It Does Not Do
• See Also

Setting It Up

Geometric acoustics is off until you turn it on.

1. Select your Pro Audio Manager.
2. Tick Geometry Enabled.
3. Leave Occlusion and Reflections on unless you specifically want one without the other.

Nothing happens yet — the simulation has no geometry to work with until you mark some up.

Marking Up a Level

You do not hand the system your level meshes. You mark up the parts that matter acoustically — walls, floors, doorways, the big surfaces that shape a room.

Two components do it:

A practical starting point: block out the room a player will spend the most time in, tag its walls and floor, and listen. You will hear the difference immediately, and you can decide from there how much of the rest of the level is worth marking up.

Choosing Materials

Every piece of geometry carries a material preset. Fifteen ship, in three useful groups:

The soft-barrier group is worth knowing about. A curtain across a doorway does not silence what is behind it, it dulls it — the effect people usually fake with a low-pass filter. Here you get it by picking the right material.

If none of the presets fit, Custom exposes all seven coefficients directly.

Tuning Occlusion

Two modes:

• Raycast — one ray. A sound is occluded or it is not. Cheap.
• Volumetric — samples a sphere around the source, so sound leaks partially around edges. Costs more.

If occlusion sounds like a switch flicking as the player walks past a doorframe, use Volumetric. That partial-occlusion behaviour at edges is exactly what it exists for. Occlusion Radius controls how wide the sampled sphere is.

Tuning Reverb

Reverb comes from the geometry around the player, and updates as they move.

Two behaviours that are deliberate, so you do not go hunting for a bug:

• It eases between rooms. Walking through a doorway blends the reverb rather than snapping it. Reflection Smooth Time controls how long that takes — set it to 0 if you want an instant change.
• It does not get quieter as you walk away from a sound. The room sounds like the same room wherever you stand in it, while the dry sound still falls off with distance. That is correct, and it is what makes a large space feel large.

What It Does Not Do

• Reverb cannot tell your room from the one next door. It is computed around the player, so a sound sealed in an adjacent room still feeds the same reverb.
• An occluded sound still feeds the reverb. Occlusion muffles the direct sound; it does not stop the source exciting the room.
• It only knows about geometry you marked up. Render meshes and physics colliders are not consulted.
• There is no baking. Everything is computed at runtime.

See Also

For settings and behaviour detail:

• Framework API: Geometric Acoustics

For related systems:

• The Basics: Spatial Audio — the base layer this builds on
• The Basics: Mixing & Effects — the manual reverb this replaces
• The Basics: Audio Pro — the rest of the premium tier

Get GS_Audio

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3 - Score Arrangement

Score Arrangement Tracks are multi-layer music assets for dynamic, adaptive game music. Each arrangement defines a time signature, tempo, fade behavior, and a set of independently controllable Score Layers. This enables music that responds to gameplay — adding percussion during combat, muting melody during dialogue, or transitioning between intensity levels.

For asset structure and playback API, see the Framework API reference.

Contents

• How It Works
• Supported Time Signatures
• Glossary
• See Also

How It Works

A Score Arrangement Track is a data asset containing:

Each Score Layer is an independent audio stream within the arrangement. Layers can be enabled or disabled at runtime, creating dynamic music that evolves based on game state.

Supported Time Signatures

4/4, 4/2, 12/8, 2/2, 2/4, 6/8, 3/4, 3/2, 9/8

Glossary

For full definitions, see the Glossary.

See Also

For the full API, component properties, and C++ extension guide:

• Framework API: GS_Audio

For related systems:

• The Basics: Audio Manager

Get GS_Audio

GS_Audio — Explore this gem on the product page and add it to your project.

4 - Klatt Voice Synthesis

GS_Play includes a built-in text-to-speech system based on Klatt formant synthesis. The KlattVoiceComponent converts text to speech in real time with configurable voice parameters. Voices are positioned in 3D space and attenuate with distance, making synthesized speech feel like it comes from the character speaking.

For component properties, voice parameter details, and the phoneme mapping system, see the Framework API reference.

Contents

• How It Works
• Voice Configuration
• KTT Tags
• Phoneme Maps
• 3D Spatial Audio
• Quick Reference
• Glossary
• See Also

How It Works

1. Configure a voice using a KlattVoiceProfile — set frequency, speed, waveform, formants, and pitch variance.
2. Assign a KlattPhonemeMap — maps text characters to ARPABET phonemes for pronunciation.
3. Speak text from ScriptCanvas or C++ — the system converts text to phonemes and synthesizes audio in real time.
4. Position in 3D — the voice component uses KlattSpatialConfig for 3D audio positioning relative to the entity.

Voice Configuration

KTT Tags

KTT (Klatt Text Tags) allow inline parameter changes within speech text for expressive delivery:

"Hello <speed=0.5>world</speed>, how are <pitch=1.2>you</pitch>?"

The KlattCommandParser processes these tags during speech synthesis, enabling mid-sentence changes to speed, pitch, and other voice parameters.

For the complete tag reference — all attributes, value ranges, and reset behavior — see the Framework API: KTT Voice Tags.

Phoneme Maps

Two base phoneme maps are available:

Custom phoneme overrides allow project-specific word pronunciations (character names, fantasy terms) without modifying the base map.

3D Spatial Audio

The KlattSpatialConfig controls how synthesized speech is positioned in 3D:

• Voices attenuate with distance from the listener.
• The KlattVoiceSystemComponent tracks the listener position and updates all active voices.
• Multiple characters can speak simultaneously with correct spatial positioning.

Quick Reference

Glossary

For full definitions, see the Glossary.

See Also

For the full API, component properties, and C++ extension guide:

• Framework API: GS_Audio

For related systems:

• The Basics: Audio Manager

Get GS_Audio

GS_Audio — Explore this gem on the product page and add it to your project.