Acoustic Panels: What Thickness Actually Absorbs. A Practical Guide to Porous Absorbers, Air Gaps and Datasheet Numbers

A three-page practical guide to porous acoustic panels for home studios and listening rooms. It explains why absorption depends on particle velocity and the quarter-wavelength distance from a wall, how panel thickness and an air gap move the useful frequency range, why flow resistivity should be neither too open nor too dense, and how to read NRC and SAA figures on a datasheet. It closes with advice on how much treatment to use, where to put it, and common mistakes. You can plot the absorption curve for your own panel with the free Acoustic Panel Calculator from The Audio Stuff, and check your room's resonances with the Room Mode Calculator. More free browser-based audio tools: theaudiostuff.com/tools/.