Due to {TAIL ~ the sloping} of the truncated cones sidewall, {HEAD ~ the gap} 70 gets bigger through the length of the air horn 50 
Due to { TAIL ~ the sloping } of the truncated cones sidewall , { HEAD ~ the gap } 70 gets bigger through the length of the air horn 50
OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH