SPATIAL AUDIO WORLD
binaural · ambisonics · psychoacoustics
Section 02
Binaural HRTF Explorer
Drag the sound source around the head to explore head-related transfer functions — the acoustic filtering your ears and head apply to localize sound in 3D space.
Section 03
Ambisonics Field Visualizer
B-Format spherical harmonics decoded into spatial audio fields. Higher orders resolve finer spatial detail — drag the source to decode amplitude at any position.
Spherical Harmonic Channels
Spatial Resolution
Drag source to see decoded field
Controls
1st order: W (omni) + X,Y,Z (figure-8 pairs)
Section 04
Acoustic Environment Map
Five acoustic environments visualized isometrically. RT60 reverberation time characterizes each space — from the anechoic studio to the resonant cathedral.
Reverberation Time
2.0 s
Concert Hall
RT60 = 0.161 × V / (α × S)
Room Properties
V: 15,000 m³ | S: 4,200 m² | α: 0.29
Surface Materials
Walls: Plaster / Concrete
Floor: Wood
Ceiling: Acoustic tile
Seats: Upholstered
Floor: Wood
Ceiling: Acoustic tile
Seats: Upholstered
RT60 Guide
Section 05
Psychoacoustic Effects Lab
How the auditory system interprets spatial cues — from the Haas precedence window to cocktail party attention filtering.
Delay: 15 ms
Haas Effect
With delays of 1–30ms, the auditory system fuses the direct and delayed sounds, perceiving one sound located at the first-arrival source. Beyond 30–40ms the delay becomes an echo.
● Fusion zone — perceived as one sound
Level difference: +6 dB (delayed louder)
Precedence Effect
The first-arriving sound determines perceived direction even when the delayed copy is up to ~10dB louder. This is the basis of concert hall design — early reflections enhance the direct sound.
Attention focus: Source A
Cocktail Party Effect
The auditory system selectively attends to one conversation in a noisy environment using spatial, pitch, and timbre cues. Focused streams are perceptually enhanced; others are suppressed.
Pan: Center
Phantom Center Image
Equal energy in both speakers creates a phantom center image — a perceptual illusion of a sound between the speakers. ILD controlled by pan law determines the perceived position.
Section 06
Sound Movement Paths
Animated sound sources moving through space. Doppler shift causes frequency changes proportional to approach/recession velocity relative to the listener.
Speed: 20 m/s
Distance: 80 m
Doppler Shift
Δf =
0.0%
Path Info
Sound source orbits at constant angular velocity. Apparent position rotates 360° around listener.
Section 07
Reverb & Room Acoustics
Sabine's formula predicts RT60 from room volume and surface absorption. Adjust dimensions and materials to design your acoustic space.
Width: 12 m
Depth: 10 m
Height: 4 m
Front Wall
Back Wall
Left Wall
Right Wall
Floor
Ceiling
Calculated RT60
0.48 s
RT60 = 0.161 × V / Σ(αₙSₙ)
Decay Curve
Ideal RT60 Guide
Room Volume & Total Absorption
V: 480 m³ | A: 160 sabin | ᾱ: 0.33
Section 08
Spatial Audio Artists & Researchers
Pioneers shaping how we hear space — from psychoacoustic science to immersive field recording and object-based cinema audio.
Section 09
Glossary of Spatial Audio Terms
22 essential concepts in spatial audio, psychoacoustics, and acoustic engineering.