[Hybrid IEM's, 4BA+1DD]: FiiOs new hybrid IEMs, the FH7S earphone 1 dynamic 4 BA driver design features a 2nd generation 13.6 mm DLC diaphragm dynamic bass driver fully capable of extending to the lowest frequencies with ample punch. Mid and high frequencies are handled by a custom 4 Knowles BA setup that accurately reproduces every last musical detail. Together, these drivers provide a rich and detailed musical soundscape.