HI all, I'm new to the scene here, just got my outlaw 7500/990/lfm1 combo yesterday and have finished connecting everything and I have a problem with the subwoofer. Very little sound is emenating from the woofer, when I touch the woofer itself it is barely flexing with the volume and gain raised. I am using a sub cable with a y-adapter at one end and just plugging one into the sw1 pre output on the 990, would I need one with single plugs on both ends or is there no difference with the extra plug. I am just starting in the home audio realm and will most likely have more questions as I progress, thanks for your time and help.