Starting an open baffle three way...

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Joined 2018
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I have read lots about the woofer sections of open baffle speakers including theory and simulations, but I have not seen many builds with measurements.

I will be building and comparing a couple different versions and sharing my results.

Here is the first one, an M-Frame with two MCM 12" woofers. From reading about this type of box, I was looking for a baffle just wide enough to hold the woofer and have the base square. With a 12.5" baffle to hold a 12" woofer and using 3/4" plywood, that meant the base would be 14"x14". I am much more of a PAD (pencil assisted design) than I am a CAD person, so I cut a board to 14" wide and just laid the box out. I did have a highly technical scale drawing that I was working from. It went together well. I am not sure if I needed the cross brace dowel in the front, but this is crap aspen ply and I didn't want the sides to resonate. Since I am expecting to cross this over at 200Hz, I don't think the woofers will see the dowel.

No measurements yet.

Low root screws were used to assemble the box, all squaring cuts were done with a track saw, washers and lock nuts were used on the back side of the baffle to mount the woofers.
 

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