Hung Cao,
         Ohm's is resitance(the strain that is put on you reciver or amp)
the higher the ohms the less resistance.  When you connect them to the 
reciver along with the polks in parrall you will get a lower ohm.  In series 
you will have a higher ohm.  Parrall is Positive to positive and negative to 
negative. If you have any ? just ask.
                      Shadow
                           Jason
                       Low Rider
--- Maximus 2.02
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