Not to sure if it was belmont. Do you know his Sounddomain page?
Thunder 550
Nice box! How dose it sound? Do you have dimensions??
It's pretty loud for 10's. I have a Rockford Power bd1500 pushing them, it bench tested at something like 1650 watts RMS, but I have the gain turned down fairly low. I think my subs are rated at 500w RMS each. It sounds real clean too when it needs to.
I don't have any dimensions. I built the box about 4 years ago. All my plans were scribbled either on loose sheets of paper or on the box itself anyway. I have told people before that I would measure but I've never actually gotten around to it, so I won't make the same promise to you. It's not hard to do if you're good with geometry and you can keep yourself organized.