my grandfather is having trouble hearing the birds and wildlife in his back yard. this is one of his favorite past times and its upsetting seeing him not be able yo enjoy it like he used to. he has tried hearing aids and all the new ones give him ear infections. so I let him use my impact sport amplified ear muffs and he loved them. these are the only model I've owned so I was wandering if there was a model better suited for just amplification and not necessarily reducing the loud noise. thanks for your help.