Hockey,

Rather than wearing out your ear drums in preparation for early deafness, try my system. I have foam ear plugs that knock off about 30 dB of sound. It cuts the background noise to an acceptable level.

The ones that work best in my experience are the yellow cylinder shaped plugs. To insert them, roll and twist them with your fingers. Then put them in and they will expand to close off the ear canal. They can be washed and reused by washing them in very hot water. Buy them in the bulk packs or box.

Your 'filtering' problem is more likely an occipital lobe injury, especially as it feeds information to the corpus colosum.

My occipital lobe processes information at about 25% of the normal power. This bottleneck is a big part of the problem with auditory over stimulation.