I recently had 2 Mayhem !5's put in a cut through in a my 2004 Dodge Ram. The box is tuned to 32htz. I power it off a Clif Designs 4800.1 and it hits harder and lower than anything I have ever heard (in a truck). Ascendant Audio is in my opinion the best, if the ultimate a street basser can get. Most people cant handle the sound in my truck. The shop that did the install told me that they have received several calls from "people" advising them to turn it down when in town. I have not been able to get them to distort under any bass and I pound them at all times. Its nothing but thumbs up for me, I'm sold.