No I don't use the bass boost or the loudness. I will bump up the sub level when I'm listening at low volumes on occaision, if the song doesn't have a lot of bass output. I also use the crossover adjustments on the HU as well, with the crossover adjustments on the amp turned all the way up. Just seems more accurate that way to me. Amp adjustments aren;t marked very well.
Just an FYI, Prior to using the DD-1, I used the "turn the HU volume up to 3/4 and adjust amp gains by ear" method. It proved to be way off. With the volume set at 27, the amp gains I had set about half way. Now with the DD-1, HU at 35 and amp gains set between 1/4 and 1/3. Amp ran hot before as well, so Im hoping with the gains set lower, it will run cooler.
Its a nice little device. It was my first time using it and only my second system install. Took me about 30 minutes, but I double checked everything and was reading the manual as I was going through it. Thanks for your help guys, much appreciated.