Ok I'm wondering if anyone that is running studio 40's have set them to large. Here is why I ask: I was going to set to them to small (probably still will) but I just had this CRAZY experience. I plugged all my speakers in (4 40's and a CC + velo CHT-15) I was having problems with the sub connection so I had cranked the volume to full (a few days ago, forgot to turn it down!). So anyway, I throw in my Diana Krall DVD (live in paris) and start playing it, I jumped up as soon as the first bass note hit, OMG my entire room is vibrating, I forgot to turn down the sub..... So I ran to turn it down, hmmm that's odd I didn't even turn it on!! What the heck is going on here, my speakers are set to small! What happened is I was in direct mode on my receiver (denon 4800) and it was pumping all the bass to the 40's! I was BLOWN away by how much bass I was getting it was absolutely insane, the cement was moving! I finally set them to small and got my sub on there, still sounds great, but man, I'm considering setting them to large and testing the differences, as they are certainly capable of almost everything down low. They don't do 20hz but damn near (so it seemed). So if you have 40's set to large and have been thinking of a sub, you might want to hold off You're not missing as much as you would think!