ok this is my situation i currently have a 2012 Mercedes C350 and just purchased audison fronts and audison rears , audison bit one , and a hertz hx300d 12" sub 600 watt rms 1200 peak all powered by a audison voce 5.1k 5 channel amp that has 1000 watt rms at 2 ohms for subwoofer. So i had it installed at the shop and the box was a ported custom built box with the ports on top and the sub firing towards the trunk and had the amp rack installed behind the folded down back seat. I got it back and the bass just wasnt entering the cabin at all and the rear speakers arent in the deck but in the back doors and after alot of reaserch i found that everyone says mercedes trunks especially newer are absolute bass traps. So i took it back again and had them remove the stock sub from the rear deck wich is a huge job cause you have to take everything apart. I was hoping that bass would enter the cabin better but thats when everything fell apart:( On deeper bass notes it rattles the plastic rear deck REAL bad , not that normal rattle thats accociated with normal bass doing usual rattle but like a flaping rattle and it is just unnacceptable in a Mercedes. The sharp sq bass notes are fine though but i listen to hip hop so alot of the low bass notes hit. It didnt flap rattle the rear deck before when i still had the stock rear deck sub in but i had only 400 watts running to the SVC hertz hx300 sub so it probably didnt have enough power to rattle , it started making that noise when i took stock sub out for more cabin bass and put the double powerfull amp in at same time and used the DVC HX300d instead of SVC sub so i think it will be same outcome even if i put the stock sub back in. So i brought it back yet again and the installer tried to fix it and i just got a call saying he tried doing something and it flap rattles just as bad still and now im left with a choice and this is where i am desprate for advice:worried: He said these are the choices i have A) There is a rear middle pull down arm rest that that when you pull down is this black plastic wich would lead to trunk i think if you cut it out somehow He said he can build a band pass box for the single 12" hertz hx300d and have the sub mounted sideways i think and cut out a hole in that plastic and port the band pass box directly through the hole wich he said would carry the bass right into the cabin and have no rattle on rear deck OR B) since i have a 1000 watt 2 ohms rms amp i could do 2 12" hertz hx300d in a sealed box firing at the back seats and would still cut that hole in the arm rest Also here is a few pics i found but still dont know wich choice to pick Man i dunno what to do and i need advice , i just want pound hard bass with no rattle that can enter my cabin or hit my plastic rear deck and sound well in hip hop. Im 6 GRAND into this and wanna be done with this and get my car back