2 (2x15") or 1 (4x15") and vent question

[lbunting]

Hello Eveyone,

this will be my first IB project. My new entertainment room sits on a conditioned big crawl space that communicates with my basement. I want to create an IB sub/s to vent under an entertainment center at the front of the listening area. The entertainment center will be about 5-6" off the floor, be on legs so it is open underneath and have a solid bottom. Is this ok? I read the other posts about venting under couches acting like a base trap, but shouldnt get that effect from a solid piece of furniture, right?

Also, Should I build a 4x15" manifold or (2) 2x15" manifolds? I could seperate the 2 manifolds by 6 feet, which might give a good spread. I would prefer the smaller openings of the 2x15 manifolds, as I can cover them with grates that match existing HVAC.

Our house has an open floor plan, so the new entertainment area basically communicates with my whole lower floor (~2200 sq feet) through a large arch (8x8 feet).

Thanks, Leo

[FOH]

The IB firing into the bottom of a 6" gap, ... it'll very likely work.

I'd make sure the furniture piece is substantial enough as to not resonate, vibrate, and otherwise detract from the experience. Years ago (mid/late 80's), I was blown away by the improvement in sound by the simple elimination of my A/V cabinet that contained my TV, and audio gear. By eliminating some detail smearing LF ringing, and improved imaging by lessening the early/diffractive reflected energy off the big, acoustically dominate piece, the output clarity and detail heightened significantly.

As to whether you utilize one 4 driver manifold, or two 2 driver manifolds, whatever is easiest. You may have some acoustical optimization advantage with the separation between the sources, but that remains to be seen. I'd pursue the two manifolds, in case the four drivers didn't possess the total output capability you may want. Thus, easier retro fit into doubling the drivers in the future.

If the IB system acoustically "sees" the entire cubes of the open floorplan, then yes, you may encounter a situation whereby the 4x15 IB has the quality you want, but operates on the ragged edge risking bottoming, etc..

What mains will it be mated to?
Distance from IB to LP?
Dimensions (w/ceiling height) of said entertainment area?
Any pics would be helpful too


Good luck

[brady]

Hi

This could work but the problem is the bottom of the entertainment center will vibrate like mad.

I helped a friend install a line array firing through a custom built entertainment center, even though the opening was plenty big we had to line the entire space with 2- 3/4" layers of mdf some bracing and green glue to silence it.

[ThomasW]

+1

[FOH]

It all depends on one's definition of "solid bottom", .... being mindful this is an IB enthusiast's forum


"5-6" off the floor, be on legs so it is open underneath and have a solid bottom"


Any pics of said piece?