flush fit sub install

[bobgenie]

I'm a new member here so firstly I'll hello to you all

I've been discussing installing some acoustics to my room on studiotips and have been getting some great advice though it's difficult to assimilate for my little brain

I want to build a super bass trap as suggested by Eric Desart however due to limits on space I really want to set my sub(s) into the bass traps so the face fits flush. They are front firing/ported SVS PB10. I'd like to use two but will stick with one if i must.

I have SPL, and BFD Pro FBQ2496 on it's way. I also have a PC in the room so will be able to make use of REW.

At the moment I use sub 1 position for my sub and it's (OK). My guess was that if I simply install the sub(s) and build into the wall I can set it all up nicely with the BFD, or am I being too optimistic? I wouldn't be able to move them once fitted of course.

Will the BFD run two subs or will I need two BFDs?

Sketch attached and many thanks in advance as alll advice gratefully received.

Bob.

[Derek]

What kind of bass traps are those? Fiberglass absorbers or resonators? Personally I wouldn't do it because bass trapping is about how much area you will use. Those subs look like they take up a lot of area. Could you mount them flush in the ceiling in front of the fireplace? If you didn't already own the subs, I'd say an IB sub in the ceiling would be perfect for you. But then again, I tell everyone they should have an IB sub.

[bobgenie]

Right, the grey shaded area is the bass trap. It is basically a broadband absorber using RWA45 rockwool. I will be building a 300mm deep wall across the alcove with cavity behind. I would prefer not to lock the sub in but due to size and space constraints don't have a lot of choice really.

I could not fit them in the ceiling however the floor's a possibility.

Cheers

[Sonnie]

Hey Bob and welcome to the Shack!

The BFD will easily accomodate two subs in a variety of ways.

Is the bass trapping something you will have to build when you install the subs or is there someway to come back and add it later?

I ask this because I wonder if you really need the traps and have some way of testing them to determine if they will even be effective in the LFE region... particularly below 100hz. I would probably try the subs free standing before I even built the walls and take some measurements to determine what's going on with interactions in the room first.

[bobgenie]

I will measure the room before installing the bass traps, As a matter of interest, while my sub is front firing i was offered a down firing sub SVS PB12. Would this be easier to place than front firing?

Cheers,

Bob.

[Sonnie]

That's a good question... I don't really know myself, but I do have two of the PB12-Plus/2's, both placed symmetrically in my front corners of the HT room, not too much different from what you are doing. You would obviously have no options as aiming the sub and it would make it more difficult (I would think) to flush mount them in the wall, if you end up wanting to do this.

Maybe we can get one of the guys from SVS to chime in.

[bobgenie]

Now that's a lot of bass

No I wouldn't flush fit them as my feeling is that down firing subs could be sited more easily than front firing - of course i could be wrong.

I looked at some data from the Harman white papers last night which seemed to indicate that two subs sited mid distance on the side walls was best so I guess the best thing to do is site em and start measuring until i find the sweet spot

Bob

[jagman]

People often site the Harmon white papers but rarely do you see someone posting their experience with trying it. If you do try it, please post your impressions. It would be great if you could take measurements at several locations throughout the room. If not, at least walk around while playing test tones and see if you notice less differance from one location to another.