I have a single 10" P2. Works ok, but if i turn the gain, or radio volume up too loud, the bass actually gets quieter and sounds horrible and seems like it would ruin the sub fairly quick. is this the "boomy" term? or is this a reverberation effect? My box is on the small side of what it should be. I will be adding polyfill to it to see if it will sound better, but though i would check with the experts here first. thanks in advance.