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18sound 15inch push-pull.

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    Posted: 10 July 2019 at 12:07pm
Hi Guys

I am trying to understand a little design feature on this 18sound dual 15 enclosure. 



Why would you put the port mouth further in front of the baffle?
Simply because of the port length needed, or does it have any meening regarding phase issues and so on? 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote mobiele eenheid Quote  Post ReplyReply Direct Link To This Post Posted: 10 July 2019 at 5:38pm
If you don't, the port will interact with the cavity in front of the baffle. This creates a form of series tuned sixth order band pass. Technically at this point, it's still a form of parallel tuned sixth order band pass but the cavity resonance (which makes it a sixth order) is just out of the subs pass band.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote FOO Quote  Post ReplyReply Direct Link To This Post Posted: 10 July 2019 at 6:42pm
Aaah okay that makes sense 🙂
Like on Dynacord's F18 PWH with the port mouth in the baffle.

Would it do any major difference pulling the ports further out, like 30mm from the front edge?
I know it will free up a bit more volume in the enclosure, but besides that.
The extra added volume could be used on more bracings, making it bombproof :D
Maybe use four large 4" ports instead of slotted ports? That would make it a even easyer build.
Same port length and cross sectional area. 

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