Wouul it be worth it

[chambers1517]

I have a room that is about 13.5x28. It has a 4 ib3 18's in an ib at the front of the room. There is a pair at about 25% and a pair at about 75% on the front wall. What I am considering is building a pair of boxes and putting them in the rear corners. I would put a pair of ib 18's in each box 45 degrees and then screw the boxes into the corners. The rear of the room has a 2 step riser. The first step is 16' deep x13.5 wide x 8" tall and the second step sits on the back half of the bottom riser and is 8'x13.5x8". I could cut holes out under the bottom of the rear Ib boxes and use the risers as a rear ib box. The risers have some pink insulation in them and would basically be one big box. I have Audyssey x32 and the rear ib would have its own seperate calibration. What do you guys think. There is currently a 2" gap along the front of each riser to try and act as a trap. I would seal this up. Would the rear ib be an improvement over this riser trap.

[ThomasW]

Got measurements?

Why 25% /75% output settings.

Might build a couple of sealed test boxes and do measurements with them at the rear of the room

[pitviper33]

I assume that your 25% and 75% numbers are referring to physical spacing of the drivers, not to signal or output level. Correct?

I can't really image you're hurting or output in a room that size. The only reason to add some drivers in the back would be for some room smoothing. Do you need room smoothing? What's your seat to seat variation look like right now?

If you haven't measured, take Thomas' advice and do it. It's far cheaper, faster, and easier than installing more drivers. And it'll give you the information you need to know whether it's "worth it".