Research in Europe shows that quiet asphalt reduces highway noise by 3 to 5 dB(A) and more.
Quiet pavement technologies include Porous asphalt, Double-layered porous asphalt, and fine-graded surfaces. Noise reductions of 3 to 6 decibels are common.
Reducing noise by 3 dB(A) is about the same as doubling the distance from the road to the listener, or reducing traffic volume by 50 percent
EAPA Paper Abatement of noise