I've been lurking here for what seems to be forever. So I bought a Quatro 15 because it was on sale until about an hour ago. I also bought a port for it. I wasn't going to do anything until spring, but anyone reading this probably knows what happened over the last 24 hours or so. For those who don't, PE put the speaker on sale for its Deal of the Day. This leaves me with two questions: 1. Which is the better amp, the 300-794 or the 300-804? Or might there be a better alternative? I'm looking at building or having a 5.5 cubic foot box built. It will go in my basement, which is about 26.5 X 20. I rarely listen to anything much louder than 85 db. It will be about 12 feet from wher I usually sit and in a corner. 2. Messing around with a calculator, I figured that a box about 22 x 22x 26 would work. Am I even close. I don't know exactly how to compensate for the driver, amp and bracing. OK. Three questions; 3. Once it's up and running, do ou think I'll notice much difference between it and my present sub (Dayton DLS 10, aka, Tiny Mity)? As you might surmise, this is my first venture into DIY. Thanks in advance.