I did that Jim. I just set sub level on head unit to max +6 at 100 hz xover at volume 45. 12 db slope. Amp xover at 80 hz and playing the 50 hz test tone I got 40.6 v on dmm. And that is with gain all the way up. But also with the sub level on head unit at max. Is something wrong with the amp? It seems like every time I pull something out the closet it turns to crap on me. Lol. I'm looking into a saz1500.1 if this one is crap.