Transmission Loss (TL) is the frequency-dependent measure of how much sound an element blocks, in dB. Learn how it is measured and how STC and Rw are derived from it.
Sound absorption is measured in a reverberation room per ISO 354 / ASTM C423. Learn the method, the specimen requirements, and how the absorption coefficient is calculated.
Sound absorption reduces echo and reverberation inside a room by converting sound energy into heat. Learn what it is, how it is measured, and how it differs from sound insulation.
α is the frequency-dependent absorption coefficient; NRC, SAA and αw are three different single-number ratings derived from it. Learn the exact differences.