Has anybody has ever seen passive radiator that could be used for rear deck. I mean. I have speaker hole on my rear deck that has been used by midbass drivers until a few days ago when i used one of those to replace on that was in my front door. so then i had nothing covering the holes and I gained noticeable subwoofer presence, i mean 2-3 dB. But I also hear everything that happen in my trunk too. My idea would be to use passive radiators that would radiate the bass, but limit the rattle and exhaust sound. is there any 6½ passive radiator that exist or i'm better built some from speakers?

hmm.. something new for me. :o