In this video, I do a little experimental DIY improvement to an aging set of Howard Leight Impact Sport ear protection. With all the empty space inside, it seems like adding some mass to the voids should improve the noise reduction rating (NRR).
In part one of the two-part series, I cover disassembly and detail the improvements made. I used different materials on each side of the headset and will compare to see if one type of material performs better than the other.
https://www.youtube.com/watch?v=p6fdpgusSzg