speaker problem, no tweeter sound

[Lt. Aldo Raine]

ok so, my grandpa has a pair of bookshelf speakers that are just sitting there, audiosphere research,ive never heard of this company, so i thought i would hook them up as my surrounds and see if they sound better than my htib sonys that im currently using, so i hooked them up, and there is no sound coming out of the tweeter, everything's coming from the woofer,if that's even possible..., it doesn't have four binding posts on the back like most bookshelf's now a days, just two spring loaded ones, whats the problem, is there something not connected inside properly?, or are they just crappy speakers?, i was looking forward to using these cuz they look alot nice then my current ones
even tho they are not fully working i thought they sounded pretty good....
thanx