Cleats and internal volume

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Greetings! My spring project is to build the Avebury speakers from Woden Design (with Alpair 12P drivers). I've had the plans for almost a year, having had trouble locating suitable Baltic Birch (being lazy didn't help). To get my head around the assembly steps, I modeled the speakers in 3D.

I am planning to add a continuous cleat around the inside front, to attach the speaker board to (and possibly make removable). As you can see in the attachment, the cleats (in blue) add about 90 Cubic Inches of volume.

As for my question... Should I make any adjustments to account for the extra 90 cubic inches? If so, in what dimensions? Or, is this too small a value to be concerned with? I don't know enough about speaker design to know if this matters...

Thanks!

Full size image here: http://www.diyaudio.com/forums/gallery/showfull.php?photo=9864
 

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Do use hardwood for the cleats. hardwood cleats adds some bracing

I read this as Do not use hardwood for cleats 3 times, until I read it one one word at a time. Didn't make sense for a while :)

Anyway, I am very interested in this project. I have thought long and hard over this project specifically and would love to know how it comes out.

I built a pair of the Lotus^2 with CHR-70 gen II some time ago and I genuinely love them. I want to move them to the bedroom and want something with more authority for the living room.

Robert
 
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While the two are closely related, with a manifold "horny" design of this nature, I's surmise that altering the net CSA (Cross Sectional Area) of any segment could be more significant than the change in overall cubic volume - so definitely check with Dr Moose.

To echo the earlier comments, the Avebury is a substantial sized enclosure on which I'd be concerned about making the entire front baffle removable. There is rather a lot of bracing supplied by the several folds of lateral panels, and I'm not sure that much if anything would be gained by the addition of cleating for the full length front.
 
Hindsight and all, I forgot to ask ealier - is there a particular reason that was expressed in the first post as to why you'd want to make the front panel removable?

I can certainly understand that in cases such as the Pensil series of MLTLs, in which several builders (myself included) have found that fabricating with removable back panel is very handy for adjusting quantities and distribution of damping materials, but IIRC, such fill is not specified in any areas of the manifold designs other that the driver chamber?

Other than vibration/rattling, which sturdy cleated fastening of removable panel could mitigate, the major "issue" that I could see arising would be air tight seal, which would be very important in the first and presumably highest pressure section of the folded path. Again, that could be achieved with closed cell foam gasket tape or similar, but unless there's a bona-fide reason for extra work, I generally try to avoid it. (just as my wife)
 
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I got a response back from Scott (Very fast, great Customer Service!) He too advised not to make the baffle removable. He also indicated that the cleats would indeed affect the design (and even offered to do the calculations if I insisted on using the cleats!)

So, I am ditching the removable baffle plan. Thanks for all the great advice!

As for why I wanted to go this route, I had two reasons. First, it gave me some wiggle room on routing out the speaker hole (which I am not very confident about). I could save it for last, and if needed redo it. Second, I was wanting to caulk all of the inside joints. In Weem's "Designing, Building and Testing Your Own Speaker System" he mentioned how crucial an air-tight seal was for this type of box. By doing the baffle last, I would be able to get to all of the joints. Instead, by gluing all the middle pieces to one side I can only 100% caulk that one side. The other side can only be caulked on visible joints.
 
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