The THT will eat that sub for a snack. Its safe to say the THT will be flat to 20hz. Mine with room gain is flat to 16hz. Some are around the same to 15hz and some to only 20hz depends on your room. As far as other horn builds the onyl one thats i know that truley tested it the DTS-10 offered by danley. One of those will run you about $1400-$1500 shipped, built, and amplified oppossed to the THT $400 built, finished, and amplified. Other than that and the THT's the rest of them i have seen are more great idea's and concepts than actually have been built and tested when it come's to something for HT usage. Now there's a few decent designs that are only good at about 30hz-40hz but i wouldnt even consider one of those unless it was for a musical setup only.