I know this has probably been asked here beofre, but I am looking for some specific info to my situation: I am interested in building a Sonosub using the Shiva and have avidly followed many of the threads here on the subject. I want o build it partly for the fun of the prject, but moslty to add some good bass to my Home Theater system. I am in Canada and was pricing out all the stuff required. I already have approx 3.5 feet of 20" Sonotube which is what I want to use. Looking at the cost of the sub and all the the other supplies it is probably goign to run me $300US (excluding Amp), plus I don't own any tools so will have to buy some of them also. To get to the point... Is a 20" tube-based Sonosub with Shiva subwoofer likely to significantly outperform a the $400 SVS subwoofer? I was browsing their site and noticed there was one for $400 that is tuned to 25Hz and is 31" tall. If I am to spend $300 on driver and supplies ot build a sub based on the SVS design I would want it to outperform something I can buy off the shelf for only $100 more. I am pretty green at this and don't know where to start designing my sub dimensions (as I didn't even know what type of sub design to pick from the LspCAD, let alone know how to use it.) I am confident in my abilities to do the wood working involved, and would enjoy the project itself, I just want to know what difference I can expect. Is the Shiva driver signifcantly better than the dirver used in the SVS systems?