Echo & Reverberation - Interactive Visualization

Interactive simulation demonstrating echo and reverberation with real audio output using Web Audio API

Room Layout

Room Size: 10 m × 5 m
Sound Speed: 343 m/s

Room Parameters

0 = reflective, 1 = absorptive

Room Presets

Acoustic Calculations

Echo Delay: 29.2 ms
RT60: 1.43 s
Reflections: 8

Sound Waveform - Direct + Reflections

Direct Sound
Reflected Sound

Reflection Timeline

Mathematical Foundation

Echo Delay Time

t = 2d/v
Time for sound to travel distance d and return

RT60 (Reverberation Time)

RT60 = 0.161 × V / (A × α)
Time for sound to decay 60dB

Reflection Decay

Aₙ = A₀ × (1-α)ⁿ
Amplitude after n reflections

Room Volume

V = width × depth × height
Total room volume in m³

What is Echo & Reverberation?

Echo and reverberation are acoustic phenomena that occur when sound waves reflect off surfaces. An echo is a distinct repetition of the original sound, while reverberation is the gradual decay of multiple reflections that creates a 'tail' after the original sound stops.

How It Works

When you make a sound in a room, the sound waves travel in all directions. Some reach your ears directly (the direct sound), while others bounce off walls, ceiling, and floor before reaching you (reflections). Early reflections (within ~80ms) are perceived as part of the original sound and can enhance clarity. Later reflections create echoes and reverberation. The RT60 value measures how long it takes for the reverberation to decay by 60 decibels.

Real-World Applications

  • Concert Hall Design: Architects carefully design concert halls to optimize reverberation time for different types of music.
  • Recording Studios: Studios use absorption materials to minimize reflections and create 'dry' recordings.
  • Sonar and Radar: Echo principles are used in sonar (underwater) and radar (air) to detect objects and measure distances.
  • Architectural Acoustics: Understanding reverberation helps in designing spaces for speech (classrooms) vs. music (concert halls).
  • Audio Production: Artificial reverb and delay effects are essential tools in music production and sound design.

Listening Guide

Listen for the 'Slap'

In large rooms with hard surfaces, you'll hear a distinct 'slap' echo - a clear repetition of the original sound.

Notice the Decay

Pay attention to how long the sound lingers. Longer decay = more reverberation. Try changing the absorption coefficient to hear the difference.

Early vs Late Reflections

Early reflections (within 80ms) add spaciousness without muddying the sound. Late reflections create the 'wash' of reverb.