I used to have 3 12" Digital Audios in my old car and hit 145.7db at a comp with it. That was too damn loud it would vibrate the ground, flex the windshield, blew the seals on the back side windows, and set off car alarms along with nearly taking your breathe away. Now I rock two small 12s with my bass knob up front and usually have them up enough just to add a little bit of nice clean bass to the music and that's it.