I just finished my first DIY sub after several months of lurking here for tips and hints. I used the adire 142.5l box plans and a 12" Dayton Titanic MK3 for the driver. The box is tuned to 18.1hz as specified by the plans, and powered by the PE 250W remote amp. After finishing it up I centered the amp gain and loaded up some bass heavy movies. The first thing I listened to was the shark scene in Finding Nemo. Right away when the shark chomps his jaws when they first meet the sub distorted. It wasn't really a loud pop or clang, just a loud farty noise that sounded horrible. Later when the mines detonate again I hear a farty mess. Does this sound like the driver is bottoming? Using unibox it looks like I should be fine as far as excursion goes, plus this amp is supposed to have a rumble filter that starts at 19.4hz. Someone on the PE tech board remarked that this driver would be starved with only 250W and would easily be pushed to clip. Could this be what I'm hearing?