I posted this on HTF, but thought I may get some great feedback here.

After reading pretty much everything I can find on subwoofer placement, effects of placement on output, etc, and "stereo vs single vs one for each speaker" debates, I have been considering an alternative.

How is the sound of a sub affected if it is in its own nook? What I mean is...if I build a room in which there is a nook in the center of the front wall in which to place the sub, what will the effects be? If, for instance, I build the front wall with an indention, say three feet wide and three feet deep, with the nook's side walls coming back to the main wall on a 60 degree angle, so that the opening at the front wall is 6 feet across, what would the effects be? Would I get more, less, or the same room gain as I would if the sub is placed in a corner? Would the effects of the nook walls be offset by the fact that the sub is still placed in the center of the front wall?

If the sub could be placed this way, I was thinking that perhaps the bass would be less easily located, as my mains are crossed over at 60hz, and my center, crossed over at 100hz would JUST in front of the sub.

Would this create other problems that I have overlooked. Would room acoustics hurt a placement like this? I am building a theater room to .6 X 1 X 1.6 dimensions with about a 23 foot length. By setting it back in the nook, I could effectively lengthen the room a bit as far as reflective bass waves are concerned.

Anybody have any thoughts???

Soffit mounting is common in studios. You should see no problems as long as there isn't a large amount of room around inside the cavity where the the sub resides that would cause resonances - this could introduce peaks and dips in the response. You would get the same re-inforcement from the wall and floor gain as if your sub was not mounted inside the wall. If the soffit was in a corner, you would get reinforcement from 3 sides instead of two, and more gain.

I read your stereo sub thread with interest SH, ant that is what really made me think of this. A second sub is really out of the question for me, and I know I can hear the bass coming from the corner sub, so I thought of moving it behind the display. I can easily build a small nook behind the display in which to house the sub, giving the sub 2 corners, a floor, and a shortened ceiling in which to reinforce the sound.

You are saying that there will be no gain realized over just plain placing the sub in the center of the front wall without the offset nook area? Bass reinforcement has to do only with the boundaries of the main room?

Bill

[This message has been edited by willscary (edited October 18, 2003).]

Yes, Soffit mounting will not buy you anything, gain wise. If your subs have a port on the rear of the cabinet, mounting this way will of course block the port which is not a good thing. The only real benefit I can see is that you will have your sub out of sight.

SH...you keep saying soffit. I am thinking along the lines of a 3 sided indention, like a small closet with no door, to house my SVS cylinder sub. When I think of a soffit I think of something built out into the room, like a soffit at a ceiling to hide duct work, plumbing pipes, etc. The nook would be out of the room, and would be built with walls angling towards the room...like a big horn loaded sub. I would build it out of masonry (part of the basement foundation), and then use speaker cloth to create a seamless wall across the opening. My wife would be happy to have the sub out of sight and I could kill 2 birds with one stone.

I guess I was just hoping there would have been a sonic benefit to doing this, and perhaps a room coupling that would give me at least as much gain as corner placement does. Thanks for the reply, I guess this idea is junk.

Terminology aside, what you had in mind is what I though you did. If you have a cylinder sub, I definately would not do this, as it would be inviting cavity resonances. Corner mounting benind something would be your best bet if you need to keep it out of sight.

Just thought of something...read whole post before responding. Ooops!



[This message has been edited by Jason J (edited October 19, 2003).]

I have my SVS cylinder sub in a recessed area of 8'X 5.5'X 3.5',(hxwxd). Not to try to hide it but just because of the way my room is built. I have had crossovers set from 100 to 60 in different trials and never could locate the direction of the bass, so I'm not sure why you are noticing the bass coming from the sub. Until this can be answered I'm not sure building a recessed area will make any difference.