all i have in the system is JBL components up front and 13cm speakers in door with 12" JL sub.
the rcas are on the subwoofer pre amp connection so i can turn it up down the back roads but down in residential areas.
was playing with the EQ on the HU last nigh and when i put the LPF on the speakers it also cuts some of the frequency to the sub.
why is this, surely the filter should only affect the speakers not the output to the amp?