What is the difference between the follow shapes

[penngray]

Ceiling mounted IBs.

4 speaker cube




4 speaker rectangle.




Does the rectangle sound better because of more opening sqft.? Is the cube opening to small and will create a bandpass (4 18", 24x24 opening)

I also see OSB in the rectangle but not in the cube, will the cube have structure problems?

last newbie questions, can someone put 2 more speakers in the rectangle design on the ends or will this screw things up?


btw, thanks to other members for these great designs and solid looking boxes.

[ThomasW]

The software in this forum doesn't allow merging of threads. So the idea behind having a "My Project" section is to have one thread and ask all your questions there. That way the forum isn't littered with multiple threads all dealing with the same project and people can easily follow what's been asked and answered.

Does the rectangle sound better because of more opening sqft.?

Yes

Is the cube opening to small and will create a bandpass (4 18", 24x24 opening

Yes

I also see OSB in the rectangle but not in the cube, will the cube have structure problems?

Certainly won't be as rigid as one built per our recommendations.

[penngray]

Sorry about that,


This was simply a generic question that all newbies probably like to know. I never considered it an exact part of my project.

[chrisbee]

penngray said:

Sorry about that,

No need to apologise.

This was simply a generic question that all newbies probably like to know.

Agreed. Though I believe this matter is covered in Thomas' extensive FAQ's it does bear repeating.

The larger the opening the better for SQ. Provided the box remains rigid. Cross-bracing and the use of recommended laminations of suitable thicknesses of plywood/OSB and/or MDF/OSB should be used.

MDF on its own is not recommended due to lack of inherent strength. Anyone who has tried to use MDF for shelving will know how it sags horribly over time even when not supporting any weight but its own. It has the advanatge of being easily machined. (producing lots of dust)

The usual problem with large manifold openings is WAF (wife acceptance factor) Smaller manifold openings are better tolerated by partners. Covering screens are useful in this regard though painting the inside of the manifold to match the baffle/mounting surface is quite a good disguise.

I never considered it an exact part of my project.

It wasn't. But we like to ration useful discusson to an absolute minimum here.