Hmm, actually one more question. What is a good crossover frequency to set for those subs. I was thinking somewhere around 80 Hz? I got that number from the zapco amp pdf page 50, the competition class diagraming. It showed that amp for the sub being set to 80Hz. Also, the Rainbow Profi Vanadium 365 Kick components have a frequencey response from 80Hz - 25kHz. So all in all, that magical number 80 I got was just a speculation. I just wanted to get some verification from the professionals here.