A buddy of mine has 2 3XL 12's, paired with a 1750.1 (running 2 ohms, thought it was at 1, but he has D2 versions). Not sure what the box specs are, but it's tuned to 36hz according to the builder. He scored a 141 legal sealed, in a trunked car (rear seat down). Is that respectable? We're going to drop the load to .5 and burp it, to see what he can get. He wanted to drop it to .5 and leave it, but I told him he'd be screwed one way or another. 1. Too much power for the subs 2. Not enough electrical for .5 daily.