I've noticed that SVS recommends a pair of 16-46 subs in larger rooms. While I have no doubts that this would do the job it seems there is a better way. What about a 25-31 and a 16-46. The 25-31 will handle frequencies from 25 to the crossover on the receiver and the 16-46 can handle the frequencies below this by setting a low-pass crossover at 25. I would guess it might be a little tricky to get everything working together but it makes sense to take advantage of the 25-31's ability to produce the frequencies above 25 more efficiently. If running a plus series you could even tune the 16-46 to 12hz. Since the 16-46 is covering only the last octave or so it should be able to really belt it out. Comments?