Design a process for making the sound
A procedural sound model describes how a sound is generated. Oscillators, noise sources, filters, resonators, and envelopes can be combined to represent a particular source. Its parameters expose aspects of that source to the designer: a helicopter’s rotor speed, the firmness of a footstep, or the intensity of a fire.
Changing an input changes the generated signal. A preset stores a useful parameter state; it provides a starting point that can be edited or driven over time.
Connect sound to behaviour
Consider a character walking across a scene. Animation or contact events determine when each step occurs. Movement, footwear, and the surface inform how it should sound. Keeping timing and sound character under separate control makes it possible to change the performance without authoring a recording for every combination.
An engine presents a continuous version of the same problem. Its sound needs to follow changing vehicle state through acceleration, steady running, and deceleration. The useful design question is which controls describe those changes, and how they should move together.
In practice, map a small set of meaningful gameplay values to the model, choose their ranges by listening, and smooth changes where an abrupt jump would sound wrong. Triggered sources need event timing; sustained sources also need a clear start and stop lifecycle.
What changes in production?
With synthesis, the sound can vary at its source. Duration, spectral balance, modulation, and other properties can be designed as part of the model’s behaviour. Procedural sources can sit alongside recorded material and use the same spatialisation, mixing, and effects stages.
The trade-off is that the model must cover the sounds your project needs, and it consumes processing time while running. Evaluate the audible range of its controls, variation over repeated events, transitions between states, and the number of simultaneous sources on your target hardware.
A useful first test is one source linked to one changing input. Once that relationship sounds convincing, add further controls and test it in the scene’s mix.
Try the approach
Start with Fire, Footsteps, or Engine in the browser. Load a preset, change one control while listening, then compare how the sound behaves across its range.
From the blog
- Procedural sound models and gameplay parameters — an introduction using the Action Pack.
- Adaptive footsteps sound effect — timing, contact, and variation.
- Engine sounds for game engines — continuous control for vehicle sound.