If I am using a brush cutter creating 98db at ear (manufacturers claim) and I can still hear music from 30m away what would the db be at the source of the music. I was wearing ear defenders but presume that they would work equally on both sources of noise. I am lead to believe that the source (i.e. speakers) were pointing away from me. Does the direction of the speakers have any impact? What are your thoughts and is there a db range as an answer?