The second transducer lies in the plane of {TAIL ~ the input and output transducers} of the parent application, but faces the ear canal cavity so that it detects {HEAD ~ the residual uncancelled noise} present inside the ear canal cavity 
The second transducer lies in the plane of { TAIL ~ the input and output transducers } of the parent application , but faces the ear canal cavity so that it detects { HEAD ~ the residual uncancelled noise } present inside the ear canal cavity
OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH