Holey Brace and other vibe quellers

[901Fixer]

I've searched some and have seen various approaches to internal bracing but wondered if there is a thread that goes into exactly what to try and achieve and what to avoid design and shape wise.

I'm building an enclosure that is 18.375" wide x 12.25" deep x 48" tall internally. I have made a holey brace to run front to back between the front and rear panels/baffle from top to bottom. This will support the magnet with a lip underneath it and is snug up against the back of it. What about bracing from side to side? I got some 1" dowels to run from left to right between the sides and thru the holey brace, will these suffice or help? Are holey braces better to use in this area as well?

[MJL21193]

Hi,
You should consider another 2 holy braces that run vertically, between the middle brace and outer panel, splitting the side panels into two unequal sizes.
Seems like more work (it is ) but beats dowels easily.

Rough (!) mspaint sketch below. Looking down from above.

[901Fixer]

Ok, so still vertical , thats doable.
I'd love to see pics of what types of patterns of cut-outs is best. I have seen the braces in the various SDX7 boxes but thought that random shapes and unequal non repeating shapes and angles were desirable. Sorta like a truss or girder but not symetrical or balanced, more like freehand so to speak.

[MJL21193]

I'd stick with round holes - a couple of common size hole saws will do it. Also, quite a bit faster than anything else and if your are doing a lot (you are), it will save some tedium.

[901Fixer]

How important is it to run the brace from top to bottom? This is a tall box, 48" tall from top to bottom and vented at the bottom. I was looking at the Shadow plan and it specs a holey brace just between the two drivers in the Push Push version but it does not extend to the top or bottom. I'm not looking for an easier way out I just don't wanna have too much that will effect performance or sound. I did include plenty of volume for bracing so thats not a concern. I will likely use my router to contour the edges of any holes or cutouts i make.

How much of the Holey Brace is supposed to be removed? Is there a ratio like remove 50% of the material from the brace or so?

The voicecoil is vented in the center of the magnet. My brace runs directly centered on the magnet and I will need to remove material from the brace in that area. Is there a preferred way to do this or is a taper needed etc. ?

I can certainly come up with these answers myself but half the time I do that there is an aspect that I had not considered so I like to run it by y'all. This Hi Fi stuff can sneak up and bite ya if you get complacent.

[mattmcl]

In the designs I've seen, 40-50% of the material is removed. The trick is to cut the brace to size, then weigh it. Keep cutting holes until you remove half the weight. If you have to make more than one of the same size, trace the holes onto the second piece to save time.

I tried hole saws with a cordless drill, and it didn't work too well for me. Probably OK with a drill press if you have one. I ended up using a coffee can and two other circular objects to draw circles on the board, then freehanding the circles with a router, it went pretty quickly and the holes invariably have more randomness.