E36/7 Z3 (1996-2002)
I upgraded my 99 MCoupe from the HK 9-speaker setup with the BSW 6-speaker replacement recently (sans door midranges, which area in their opinion worth keeping), only to find my OEM subwoofer to be kaput.
After an hour on the phone with BSW's generous tech, I found my subwoofer voice-coils were...