Subs moving, but not making much sound

Sorry if this is at all vauge or confusing. I sold my old system to my friend about a month ago (2 Orion C12s and a Power Acoustik amp). Everything worked great up untill a few days ago. Now my friend says the subs only seem to hit the really low notes, and everything else is really quiet. He says the subs are still moving as much as they did before, but they arent really producing much sound, they still do all the hits, but its to quiet to hear inside the car. He says the amp protect light has not blinked red at all, but stayed green. he says there was no distrotion or clipping before this happened,and it just happened all of a sudden. I have not yet looked the system over, and im only going by what he is describing to me. Before this he had another problem where the amp would turn on and off, it turned out that the amp turn on wire was loose in the plug that goes to the back of the HU, but i doubt that has anything to do with whats going on now. I really doubt the subs are blown, I think the amp may be shot. It is pretty beat, but i used it in my car for a year and never had a problem with it.

Yep, either the amp is fried or at least one of the subwoofer voice coils is fried, or something simple like the Xover got tweaked down to about 30Hz.Support the12volt.com

Only other thing that comes right to mind is out off phase. ask him if one of speakers came unhooked and maybe he hooked up wrong otherwise it is probably shot. throw some other speaker in ther and hook it up to see if it does it with other speakers then u know its the amp.rottenbellys 05 crew cab colorado.Pioneer dehp 880prs, kenwood excelon in all 4 doors. Bazooka 500 mono Jl 10w3 in coustom center console box.

i dont think it would damage the subs any would it.. if it's the amp.. could hooking the pos's and the neg's on the wrong terminals cause those affects?SSounds

what kind of vehicles are they in? maybe a larger car versus a small car creating different sounds...just a thought...but to me it does sound like the subs are out of phase (neg and positive backwards on one sub ) or the crossover is set way to lowTri County KustomZ

certified installer

If its a common chamber box (both subs sharing the air space) then 1 sub may be blown.2003 Chevy Avalanche,Eclipse CD7000,Morel Elate 5,Adire Extremis,Alpine PDX-4.150, 15" TC-3000, 2 Alpine PDX-1.1000, 470Amp HO Alt.

Its a 96 Towncar, but it sounded great when installed it about a month ago. I dont see how the subs could have got out of phase, but ill check into it when i look everything over. No its not a common chamber box, there is a divider.

would an ohm meter tell ya if it is blown or not?SSounds