Actually, it is possible for it to be a one way movement sub. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Or it likes to move in one way more than the other. Good common example of this is the L7 series from Kicker. They had more outward movement than inward movement, which is indicated by the natural resting spot of the coil, and if you take the spiders off, it is more stiff one way compared to the other. (Not sure about the L5s, never felt I should even be messing with them.)
Edit: After a quick glance, there is a coil. Look on the right side of the coil former. Above where the motor is, there is a voice coil. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif I was right, if that is the actual top plate. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif