Reply to I am DJing a friend's party this weekend. Help me add some BASS.

I agreed to DJ for my friend's birthday this Friday. I have been djing for about 3 years just for fun, and that's all good, but with my current set up I am lacking a nice bass sound. I currently use the NS7 hooked up to this PA System: http://i.imgur.com/nXWSVC0.jpg [1]

What is a nice way to add a sub to this system? I was looking at these, but I am unaware if it will sound okay. Possibility 1: http://www.amazon.com/Seismic-Audio-...s=PA+subwoofer[2]

Possibility 2: http://www.amazon.com/GemSound-SUB20...s=PA+subwoofer[3]

I understand these aren't the highest end subs, but I am on a budget and these are going to be used just for house parties. If I buy these will I need any other gear ? Any help is appreciated.