I've been doing a ton of modeling with the Shiva in approx. 105L tuned somewhere between 18 and 20Hz, hoping to achieve (on paper at least) somewhat similar performance as the SVS 20-39CS. I would be using the AVA250 for power. I read TN's review of the 20-39CS in TSS, and I noticed he stated that they are in 3.75 cu.ft. and use a 4"x15" port. I'm just trying to figure out how that tunes the enclosure to 20Hz. LspCAD tells me the port would need to be about 18.25" long, and this is just for a non-flared port. Since SVS uses flares, wouldn't the port need to be even longer to achieve a 20Hz tune in that volume?