DSP system sucks for bass.

I need to add a sub to my car. The DSP subs are horrible. In fact if I turn the system too loud (not even maximum volume) the subs make a horrible noise as if they are about to blow so I have to turn the volume down quickly. Sometimes the speakers do this as well, but the speakers never sound distorted.

& just to give you an idea of how bad the subs are.. I didnt even know I had subs in my car for the first week I had her.

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I would love to know how the Alpine PLV-7 sounds in your car when you install it. Are you going to keep the DSP subs as part of the system too?