What are you gambling? I mean unless the voice coils corroded and ceased up or something crazy which would be very un-likely, go and run them suckers in... Higher volume even.. Worse case is the rubber would be stiff on the surrounds, you could take a little armorall to get them a little cleaned up and softer if necessary... Its possible they have newer foam type surrounds, but still only 8 years old, and unless they were stored in really bad conditions they should be fine, then again if a lot of moisture collected in the sub amps that could be another story with never being used, I don't know.
Maybe 50 to 200 hours should open them up pretty nicely.
Good luck
Maybe 50 to 200 hours should open them up pretty nicely.
Good luck