Leaderboard

For speaker level input on any car amp tapping into (or paralleling) the existing circuit is not the proper way to do this. The head unit's amp section is designed to drive four 4 ohm channels, if you upset that impedance to the rears by adding another load in parallel into the circuit you'll cause issues for the head unit amplifier possibly causing the head unit to fail. The proper method would be to open the circuit to the rear channels & plumb in the amplifier using the left & right speaker level inputs to the amp, then reapply the left & right rear channels using 2 of the amps four channels to the parcel shelf speakers & the 2nd set of amp outputs in a bridged mode circuit to the *new* sub. To do this one needs a 4/1 or a 4 channel amp, 2 of the 4 channels out go to the rear parcel shelf speakers & the other 2 channels are bridged into 1 that go to the sub... ASSUMING the sub is a single voice coil driver, if the sub has dual voice coils then no bridging is required.