Review on SCOSCHE HY05B Harness for 2006-08 Hyundai Sonata by Craig Shah

I had a new radio in my 2006 Hyundai Sonata that had a premium audio system with a subwoofer. They supplied Alpine CDE-164BT. I made this pendant available. When I picked it up, the subwoofer seemed weak and I couldn't control it or isolate it from the other speakers. The installer has confirmed that the subwoofer is powered by the same source as the speakers on the right. I didn't understand his explanation, all I know is that I had a subwoofer and now I don't really have one. Something in the factory sub woofer had no input. how was the food before He mentioned that I might need an amplifier to power it. But reading these reviews I see that it has worked well for others and without losing the subwoofer. Does anyone know more or can explain. Thanks very much!