I finally decided to purchase the Jamo SU631K4 inwall dipole/bipole surround speakers for the rears in my 5.1 system.
I am building out a new theater in my basement and have decided to build a backbox for these speakers. Once I started planning I thought I would build the backboxes to look like columns and mount them to the wall instead of in the wall. This will give me more flexibility in design and size.

Here is where the assumptions begin. First I assume that these speakers are designed to work in a space that is 14.5" X 3.5" X 8'. I also assume that by building a rigid box out of MDF and filling it with insulation will improve the sound coming from the speaker.

Am I way off base here? Anything else I should be considering?

anyone?

There so many variables here that I don't know where to start. First, a speaker can be designed for use as infinite baffle OR for use with a back box, not both. The drivers probably have stiff suspensions because they were designed not to use trapped air in the box (acoustic suspension.) They are of the wrong compliance for a sealed box, most likely. A sealed box will change the Q of the speaker system, and probably induce a big upper bass hump, and limit low bass response because the enclosure will raise the system resonant frequency. Also, you would need to choose the correct internal damping material, and that is not an arbitrary choice. Different foams and battings react differently.

If you are set on these open-back speakers, I would fill the columns with open-celled foam and use the entire column as an enclosure, which is much closer to how the speakers were deigned to be used.

JMHO. ;)

Paul,

Thanks for the response. You raise some great points and I agree with all of them. However, if the speaker is already designed to work in the same airspace with the same type and amount of insulation then wouldn't it operate in the same fashion? If not would their be an alternative type box that would work well with these speakers? I mean could I create a type of column that would have an open back thus allowing for an IB?

Believe me, if I had the budget I would just buy Triad's all around and be done. ;)

Judson
I have also decided to go with this speaker :) I am going to be build out the columns in the next few days. I don't have the speakers yet but plan on ordering them vary soon. The Jamo site has vary little to no info on what or how the speakers should or should not be installed. They do sell a back box for there speakers but its just a plastic box that nails to the studs :( I am still doing some digging

Scott,

Very cool! They look like a decent speaker and should sound pretty good if set up correctly. Worst case, you have to redo your column for a regular speaker and use the Jamo in the family room...

Judson

I set these up in my brothers HT room about 2 years ago along with the Jamo 626 inwalls up front. I Built enclosures into the studs for these. Sounds great. Also has a Velodyne DPS12 sub.