Do Acoustic Panels Absorb Sound?

Yes, acoustic panels absorb sound: a 2 in. fiberglass panel rated NRC 1.00 soaks up nearly all the mid-range sound that hits it, and 2 in. Auralex Studiofoam (opens in a new tab) soaks up about three quarters (NRC 0.75). Keep in mind that NRC is just the average absorption at 250, 500, 1,000 and 2,000 Hz (Acoustical Society of America (opens in a new tab)). It doesn't tell you a thing about bass.

How much sound acoustic panels absorb comes down to pitch. Down at 125 Hz, that same fiberglass panel takes in only 15%.

Want more bass? Go thicker. 4 in. of the same board absorbs 56% at 125 Hz. And don't seal up the face. Rolling paint onto a 2 in. Primacoustic Broadway panel drops it from NRC 1.00 to 0.50 (Primacoustic data sheet (opens in a new tab)). Think of a sponge: clog the holes and it soaks up a lot less. The cores go head to head in fiberglass and mineral wool soundproof panels.

One catch: absorbing sound isn't the same as blocking it. Panels tame echo inside your room. They do almost nothing about noise coming through the wall, and the soundproof panels guide shows that with lab data. Panel cores are also sold as thermal insulation, which do acoustic panels help with insulation covers. There are more answers in the soundproof panels FAQ.