ZAPCO ASP-OE8 8CH OEM SIGNAL ADAPTOR PROCESSOR WITH BASS RECOVERYZAPCO ASP OE8 8CH OEM SIGNAL ADAPTOR PROCESSOR WITH BASS RECOVERY Its difficult at best to change many factory head units. In addition there are any number of features and functions that are hampered or lost if the factory head unit is removed. The ASP OE8 is an OEM adaptor designed for superior sound quality, with top end internal parts and Zapcos custom built high precision pots. It is an active device including the line converter and a signal line