When the first number of shock events exceeds an upper event threshold, a control signal is adjusted in order to adjust a frequency spectrum of {HEAD ~ noise} affecting {TAIL ~ the shock detector} 
affecting
When the first number of shock events exceeds an upper event threshold , a control signal is adjusted in order to adjust a frequency spectrum of { HEAD ~ noise } affecting { TAIL ~ the shock detector }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL