Sound Absorption Coefficient Calculator
Calculate sound absorption coefficient for materials and room acoustics
Calculate Sound Absorption Coefficient
Sound intensity hitting the material surface
Sound intensity absorbed by the material
Results
Formula used: α = Ia / Ii
Range: 0 (perfect reflector) to 1 (perfect absorber)
Absorption Coefficient Guide
Example Calculation
Material Testing Example
Material: Acoustic foam sample
Incident sound intensity (Ii): 0.9 W/m²
Absorbed sound intensity (Ia): 0.3 W/m²
Test frequency: 1000 Hz
Calculation
α = Ia / Ii
α = 0.3 W/m² / 0.9 W/m²
α = 0.3333
This material is a fair sound absorber (moderate absorption)
Common Materials
Applications
Understanding Sound Absorption Coefficient
What is Sound Absorption Coefficient?
The sound absorption coefficient (α) is a measure of how much sound energy a material absorbs compared to how much hits it. It ranges from 0 (perfect reflector) to 1 (perfect absorber), with most real materials falling somewhere between these extremes.
Why is it Important?
- •Essential for acoustic design and soundproofing
- •Helps control reverberation and echo
- •Critical for material selection in construction
- •Used in noise control and sound quality optimization
Calculation Methods
Basic Coefficient
α = Ia / Ii
Where Ia is absorbed intensity and Ii is incident intensity
Room Absorption
A = Σ(Si × αi)
Sum of area × coefficient for all room surfaces
Average Coefficient
αm = A / S
Total absorption divided by total surface area