Am I doomed to a box sub? Placement issues.

[jowlz]

Here's my deal. I am in the middle of turning my former family room into a more dedicated theater. I was pretty happy with my Mirage BPS-400 sub. Before sound treatments etc...I ran the sub at about 15% volume. After at about 60-65%. It does sound 100 times better now...but I really want more bass. I planned on building 2 boxes to put in the rear of the room with a 15" in each but the more I read about IB's the more I would like to go that route. Here is my problem. The theater is in the basement that rules out in the floor or in ceiling. My false wall for the screen is not and wont be solid. I wish I had thought IB before I built the screen wall etc..but its a little late.

I have a Behringer EP2500 amp. I also have a Feedback destroyer..but through reading I guess I wouldnt need it for an IB. I had planned on 2 15" Tempest X drivers for boxes but dont mind going to 4 for an IB.


Here are some renders of the room. The theater itself is 21 x 19 x 8 ft. Behind it is a 12' x 14' room that will be my media room. Behind that room is a door to 60 x 32 open basement. I have about 36" from the wall inside the room to the door on the right side. I have two options as I see it. I can either...put an array in the wall or a manifold behind.

Location in the theater:



What's behind the wall:


Whats behind the room:


Now my questions. I have read every thread on this forum. Great info but I am still a little vague on a couple things:

1. Is there an issue with the door being so close to the manifold or array. Meaning, its an inside wood door, not sealed. It will be just a few inches from the backs of the speakers. Also, can I put something on the door side of the speakers to give it a more finished look and to protect from things that might bump into them, without ruining the whole point of the IB?

2. I am not sure 36" wide is enough room for a manifold. Any thoughts and if possible what sized manifold? Specifically, can I go thinner and taller manifold? If 15's wont work due to space could I go with more 12's to get the same sound. I have tons of height and not much width.

3. I realize front location is optimum...what are my chances of the IB sounding good on that side wall. Seating will be 6-7' behind the array or manifold opening.

4. The walls will be covered with GOM fabric (accoustically transparent) any issues with cloth covering the opening or a frame (covered with cloth) over the array? I'm fine leaving using a vent or leaving it open..but would prefer the cloth.

5. I plan on stacked cotton bass traps in the rear corners. Anything different with bass traps with an IB vs boxes?

6. Thoughts on the Tempest X's? Should I go with the AE's instead??

TIA for any thoughts or help.

[ThomasW]

You need to test the location with your existing sub.

Plan on using a very low crossover point with a sub that far off to the side

The door will rattle in the door frame, damp it with weather stripping foam tape

36" is plenty wide

The GOM fabric will probably flap as the woofers move.

Acoustic traps for IB sub are the same as those for any sub.

I'd get 2 more Tempest -X.

[jowlz]

I will test the location.

By crossover low...do you mean with the Behringer FBD or with my preamp. I run 6 full range speakers and a very large center. I crossover now at 40hz. Should I crossover differently?

Any problem with building the manifold out of Red Oak instead of MDF? Or can I veneer the inside of the MDF with red oak?

By get 2 more Tempests...I assume you mean 4 total..If you mean 6 total...how would I wire them to the proper ohm load or would I need another amp?

Thanks again for the info and the great board.

[ThomasW]

A BFD has no crossover functions.

Use the sub out from your pre/pro

4 Tempest-X total

Oak ply is fine