I would love to build a Sonotube just because, but space is a big issue. I have satellites on the sides of my RPTV, a hallway on the left, the my current subwoofer on the right under the satellite, and a wall-mounted flexyrack for my components, and then a closet right next to the sub. I am limited to a space of about 20"w x 15"h x 16" for a new sub. I cannot use downfiring because of the feet needed. It also has to be within 8" of a wall, so it cannot vent to the back. I mainly want it for HT, and was considering a PE 10" Titanic MKII in a 1.9cu ft box, 2" vent at 5.4" long, off to one side. F3 to 27. (As told to me by a PE tech). I was looking at the Shiva 12 and they have 54 liter sealed box plans and I could lay the box on its side and do a front firing setup, with a Q of .707. Pairing either up with one of the 250w plate amps. My question is which is the wiser choice for a HT setup? I want the cleanest, tighest sound I can get. If it gets down in the low 20's I would be happy.