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PostPosted: 11 Sep 2013, 11:14 
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Joined: 10 Sep 2013, 10:48
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What's the DIY method of creating them? Do they have to be really accurate or only roughly cut to fit in the drivers?
Also, page 2 in the design says '1/2" Bevel (Typ.)' - what's the bevel for and what's the diy way to cut it?
http://www.speakerdesignworks.com/MiniS ... 091007.pdf

This is my first speakers project so excuse me if my questions are really elementary...


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PostPosted: 12 Sep 2013, 18:21 
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Hi Krusty,

For cutting holes, I will use a hole saw kit if possible (I'm terrible with router) otherwise for odd sizes I will use a router with a jasper circle jig. The cutout should be fairly accurate as it is important that there are no air leaks. Since you will use some sort of gasket / caulk you don't have to be exact.

The bevel is a "chamfer" of the baffle behind the rear of the driver. The purpose is to allow for good airflow from the rear of the driver into the enclosure. You can see an example of mine made using a router - Photo 1: http://diyaudioprojects.com/Speakers/Fo ... ss-Reflex/

You need to bevel the edge because the baffle is 1-1/4" thick so not to restrict air-flow from the woofers. Best way would be to use a router. Without a router I have used a wood file (rasp). See Photo 2: http://diyaudioprojects.com/Speakers/BD-Pipes/

Hope this helps.
Cheers

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PostPosted: 12 Sep 2013, 22:23 
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Joined: 04 Jun 2008, 20:59
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Location: Arizona, USA
I use a Jasper jig and router as well.

Good listening
Bruce

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PostPosted: 13 Sep 2013, 16:42 
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Gio wrote:
For cutting holes, I will use a hole saw kit if possible (I'm terrible with router) otherwise for odd sizes I will use a router with a jasper circle jig. The cutout should be fairly accurate as it is important that there are no air leaks. Since you will use some sort of gasket / caulk you don't have to be exact.

The bevel is a "chamfer" of the baffle behind the rear of the driver. The purpose is to allow for good airflow from the rear of the driver into the enclosure. You can see an example of mine made using a router - Photo 1: http://diyaudioprojects.com/Speakers/Fo ... ss-Reflex/

You need to bevel the edge because the baffle is 1-1/4" thick so not to restrict air-flow from the woofers. Best way would be to use a router. Without a router I have used a wood file (rasp). See Photo 2: http://diyaudioprojects.com/Speakers/BD-Pipes/

Thank you Gio, very informative post indeed.
Could the chamfer be created with round files in mdf?
Why does the "Statements" have a double baffle in the front? Why not use a single board?..
Now, which damping matterial did you use? I prefer to use a not specialized acoustic material to keep costs down...


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PostPosted: 16 Sep 2013, 16:54 
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Yes, you can use a round file, just like I did with the BD-Pipes. Don't scour the wood away too much where the drivers are fastened in place.

The thick front baffle is for increased rigidity (so the baffle won't flex).

For low cost damping material I use polyester fill (polyfil) from Wal-Mart (sewing / crafts section).

Cheers

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PostPosted: 21 Sep 2013, 12:27 
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Thank you for your help.

Quote:
The thick front baffle is for increased rigidity (so the baffle won't flex).

The baffle I have is 5mm thicker than specified. Will it create a "sonic tunnel" affect? Will chamfering around the edges it be a good idea?

Quote:
For low cost damping material I use polyester fill (polyfil) from Wal-Mart (sewing / crafts section).

I saw in some guides "pink glass fibers" are recommended. Will it be as good?


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PostPosted: 22 Sep 2013, 10:25 
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Fibreglass insulation has been commonly used in the past. Less so nowadays due to the heath issues around it and the wide availability of synthetic materials. Insulation should work fine. Be sure to "tease" it to fluff it up somewhat.

With a really thick baffle, the chamfer becomes more important. You don't want to restrict airflow behind the driver so you will have to size the chamfer accordingly if you are going to use a thicker baffle.

Cheers

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