{HEAD ~ A throat device} for interconnecting {TAIL ~ at least two drive units} and a horn is provided 
for interconnecting
{ HEAD ~ A throat device } for interconnecting { TAIL ~ at least two drive units } and a horn is provided
HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH