Descrição
Planetary Dispersion is a procedural sound system for Unreal Engine that models dispersion, absorption, and temporal behaviour across speculative planetary atmospheres. It lets you explore how sound propagates through different media, from thin Martian air to the dense atmospheres of Titan and Venus, as well as fully liquid environments.
Frequency-dependent absorption, time-of-flight effects, and low-pass filtering produce subtle but perceptible differences. These effects are most noticeable with broadband sounds, allowing comparisons between realistic, cinematic, and stylised atmospheres.
Video Walkthrough
Watch a full demonstration of Planetary Dispersion here:
Planetary Dispersion Video Walkthrough
This walkthrough demonstrates planetary atmosphere presets, dispersion, absorption, filtering, distance delay, wind, seismic sound, reverb, and air-column tuning in Unreal Engine.
Planetary Presets
Planetary Dispersion includes a collection of scientifically inspired planetary, lunar, and exoplanetary acoustic environments. Each preset models unique propagation characteristics based on atmospheric composition, density, pressure, temperature, and speed of sound.
Jupiter – Hydrogen–helium gas giant with very high sound speed, low atmospheric absorption, and efficient high-frequency propagation.
Mars – Thin carbon dioxide atmosphere with low pressure, reduced sound speed, and noticeable high-frequency attenuation.
Earth – Terrestrial reference atmosphere representing familiar acoustic behaviour.
Venus – Extremely dense carbon dioxide atmosphere with strong high-frequency absorption and efficient low-frequency propagation.
Titan – Dense nitrogen-rich atmosphere containing methane, producing slower sound propagation and significant high-frequency damping.
Moon – Vacuum environment where airborne sound cannot propagate.
Saturn – Hydrogen–helium gas giant with propagation characteristics similar to Jupiter but distinct absorption and dispersion behaviour.
Europa – Extremely tenuous oxygen atmosphere with near-vacuum conditions, resulting in minimal airborne sound propagation.
Io – Volcanically active moon with an extremely thin sulfur dioxide atmosphere, producing highly limited airborne sound propagation.
Neptune – Cold hydrogen–helium–methane ice giant with very low atmospheric temperatures and distinctive propagation behaviour.
Pluto – Dwarf planet with an extremely thin nitrogen atmosphere, resulting in weak airborne sound transmission and rapid attenuation.
WASP-121 b – Ultra-hot gas giant exoplanet with extreme atmospheric temperatures and very high sound speed, producing distinctive propagation characteristics.
Sci-Fi – Stylised atmospheric model with exaggerated dispersion, filtering, and propagation effects for creative exploration.
Neutral – Unprocessed reference preset for direct comparison with the simulated environments.
Test Sounds
A diverse collection of reference sounds is included and can be cycled using the 0 key. The collection features pink noise, sine tones, percussion, piano, strings, brass, woodwind, clarinet multiphonics, and key clicks. Together, these sounds demonstrate how different source materials respond to planetary propagation, absorption, dispersion, pitch, and atmospheric filtering.
MetaSounds, Patches, and Presets
The system uses Unreal Engine’s MetaSound architecture, with referenced MetaSounds and modular patches processing sound in real time.
Presets store planet-specific parameter sets, including speed of sound, absorption, base LPF, atmosphere intensity, water intensity, pressure, offset, and transition time. This makes it easy to switch between environments or return to default states.
Gas Composition Widget Menu
The Gas Composition widget provides additional control over the atmospheric mixture used by the simulation.
Users can enable or disable gas-composition processing, select composition presets, and adjust the proportions of individual gases. These values contribute to the system’s procedural acoustic calculations, allowing custom gas mixtures to produce different propagation, absorption, filtering, and speed-of-sound characteristics.
Batch Processing
Batch-processing tools allow multiple inputs and planetary configurations to be processed in sequence.
This supports efficient comparison, parameter evaluation, and data generation without requiring every operation to be configured manually.
JSON Import and Export
Complete widget configurations can be exported as JSON files and restored later. Exported settings are stored in the Saved/Reports folder, while a drop-down menu provides quick access to available JSON files for importing.
This allows planetary presets, gas-composition values, propagation controls, environmental settings, effect states, and other widget parameters to be saved, transferred, compared, and reused across sessions.
Custom Planetary Sound Controller
The central interface for the simulator is a fully customisable widget that allows users to adjust propagation parameters independently.
Features include:
Air / Water / Water Intensity – Select or blend media and transition between atmospheric and underwater propagation.
Seismic – Adds a low-frequency seismic layer for quake, volcanic, geological, or subsurface rumble effects.
Environment Type – Selects reverb and spatial environment presets such as ice chamber, canyon, or open terrain.
Pressure – Adjusts dense atmospheres to alter speed of sound and high-frequency damping.
Temperature – Changes the acoustic profile by affecting propagation speed and tonal response.
Humidity – Shapes absorption and damping behaviour, particularly at higher frequencies.
Altitude – Simulates height-dependent atmospheric thinning, changing the perceived density and filtering of sound propagation.
Wind – Adds planetary wind ambience, with selectable wind layers for different atmospheric conditions.
Flux – Introduces ongoing movement or instability into selected parameters, creating more dynamic and less static planetary sound behaviour.
Speed of Sound – Controls propagation delay and spatial separation cues.
Atmosphere Intensity – Scales the overall strength of atmospheric propagation effects.
Amplitude Contrast – Controls how strongly loudness differences between planetary environments are exaggerated or reduced.
Base LPF and Offset – Fine-tune spectral behaviour, frequency weighting, and band-based dispersion.
Transition Time – Controls how rapidly propagation parameters update during changes.
Record / Playback – Captures sounds directly within the system and plays them back with planetary effects applied.
Bypass and Dry/Wet Slider – Provides instant comparison between raw and processed audio.
Atmospheric Tuning / Air-Column Shift
Atmospheric Tuning applies a pitch shift based on the speed of sound in the selected planetary atmosphere.
This is intended for air-column sound sources such as voice, flute, clarinet, saxophone, trumpet, trombone, and other resonating air-column instruments. The effect changes the tuning while keeping playback speed unchanged.
Voice Formant Colour
Voice Formant Colour applies an optional vocal-colour effect after the air-column pitch shift.
It does not deliberately transpose the source audio. Instead, it moves a set of formant-like resonances using a Biquad filter bank, allowing the voice to sound darker, brighter, larger, or thinner while leaving the main pitch-shift path unchanged.
This is an approximation rather than true vocal formant analysis or resynthesis.
Interactive Features
Move the listener to adjust distance while propagation delay, filtering, and related parameters update dynamically.
Switch between planetary environments to compare their acoustic characteristics.
Adjust individual parameters to create realistic, cinematic, or stylised atmospheric models.
All audible changes are generated through the system’s atmospheric and propagation processing rather than separate planet-specific source recordings.
AI Usage Disclosure
A generative AI image tool was used solely to create a decorative UI frame element.
All audio content, sound systems, MetaSounds, Blueprints, and design decisions were created manually by the author.