The switching frequency has {HEAD ~ an audible frequency range} that results in {TAIL ~ unacceptable audible noise} that is reduced by the present invention 
results in
The switching frequency has { HEAD ~ an audible frequency range } that results in { TAIL ~ unacceptable audible noise } that is reduced by the present invention
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH