I got a replacement woofer for my c-5.  Two woofers stacked.  when i pulled them out i didnt know which wire was positive or negative, one set has a yellow and white and the other red and black, anybody know? 

Hi KingAsif

The lower woofers get the red and black. Red is positive See woofer chassis for "+" mark.

The upper woofer is yellow and white; yellow is positive.

Just to be sure put a AA battery to the rear terminals when completed, both should move outwards when you connect the "+"(battery) to "+" (speaker) .

This is safe "phase " test and will not harm the speaker!