The filter system filters {TAIL ~ the excursion signal} to remove unwanted frequency components from {HEAD ~ the excursion signal} 
The filter system filters { TAIL ~ the excursion signal } to remove unwanted frequency components from { HEAD ~ the excursion signal }
OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD