6.Connect all line inputs and outputs (if used) using
7.Insert fuse(s) into the battery fuse holder(s).
8.Recheck all connections before powering up the subwoofer.
9.Set all level controls to minimum position, and set all crossover controls/switches to the desired frequency points.
10.Power up the head unit and the
subwoofer. Then set the volume control on the head unit to about 3/4 volume, and adjust the subwoofer's input level controls to just below the level of distortion.
11.Further fine tuning of the various controls may be necessary to obtain best results.
Don't misuse the level control!
Do not mistake the input level control for a volume control! It is designed ONLY to match the output level of your audio source to the input level of your subwoofer.
Do not adjust this input level to maximum unless your input level requires it.
Ignoring these instructions will result in an input overload to the amplifier in the subwoofer, and excessive audio distortion. It can also cause the protection circuit to engage.
BASS1000 Amplified Subwoofer User’s Manual - page 5