EF/FEF series balanced armature speakers

The staple receiver for modern BTE hearing instruments, the EF series represents a precise balance of output power and compact size. Its length-width-height ratio provides an optimum fit that helps maximize BTE space and layout considerations while still providing superior acoustic output. A full range of Knowles' PantographTM, FerrofluidTM, and Vibration IsolationTM technologies help maximize the EF series use for any BTE instrument design. The FEF receiver brings the advantages of Ferrofluid damping, including reduced receiver vibration and improved shock survivability. These advantages are added to the EF receiver's precise balance of power and compact size. A full range of Knowles' PantographTM and Vibration IsolationTM technologies help maximize the FEF series optimum fit and superior acoustic output.


Balanced armature speakers EF/FEF series
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Product Families Model ID Dimensions Sensitivity Port Location Imp @ 1kHz Imp @ 500 Hz Ferrofluid MPO 500 MPO Pk Downloads
EF/FEF EF-21942-000 7.87mm x 5.59mm x 4.01mm (.310in x .220in x .158in) 125 12S 641 250 No 121 139
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