@chedwin Thanks! This is pretty much the information I was hoping for. It is really making me lean even more towards a sealed design. A ported design with the Stereo Integrity HT-18 V3 just doesn’t seem to make sense without a huge box as Nick already mentioned, and the cost is so reasonable for an 18 it is hard to pass up and go with something like the MX15 or Ultimax 12, etc. The mx15 will play a little louder in the 15 to 35hz region but this 18 will play sub 15hz much louder which I think I am comfortable with that tradeoff. Plus I will be eq’ing the 20 to 100hz down to help flatten the curve a little more seeing that 2 of these will be more than enough for my room.