Thanks again. I just now finished resetting gains on my system. This time I used Signal Generator by mediapunkstudios.com app on my iPod since I only ever use that source. The DD-1 picked up 41hz 0db as 40hz and 1002hz 0db as 1000hz, not that it matters, just a little trivia. My Pioneer media/cd head does not distort with 1000hz even when maxxed out at 62. The 40hz distorts at 59/62 so I use 58 as the max clean volume. Set the amp gains with 0db also, since my 10" downfire sealed sub gets a tad too loud for me when Kid Rock, Michael Jackson AfroJack edit, some others comes on. I love the way my system sounds now. Some songs I have to turn the sub down from +6 to 0 and still shakes the mirrors well.