For those who are anxiously waiting for their passive radiators, I thought I'd let you know that I recieved my 2500g 18" PR's today. Okay, now that I've said that... THESE THINGS ARE HUGE!!!! I've spent an inordinate amount of time just looking at them and gently shaking them back and forth to see the cone move. I'm convinced they are a necessity for happiness, I just didn't know it until now. My dual shiva sub is sulking in the corner, feeling woefully inadequate. Even my girlfriend was impressed! Anyone know the internal displacement (to subtract form box volume) for these guys?