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Listener of Music
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How do I calculate effective port length when doing 45s?
Your basically taking chopping the 45° angle off the inside conrner and putting it on the outside. Not really changing anything but turbulence.

You do change the length a bit when 45ing the inlet and outlet. There's an exact science but I just add a half inch if I do both ends of a 3/4" thickness board.
 

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a 1” wide port? a port that long & narrow is just asking for trouble. i’d look long and hard at things like port velocity and delay before i built it.
 

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As I like PRs... this a somewhat difficult thread to look at.
 
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Discussion Starter #24
I’d make the box slightly bigger, that’ll make the port shorter. Upsize the box using the first design until you can eliminate the first leg of the port, I bet the box ends up only slightly bigger overall and you can keep the low tune.

Basically I sort of agree with platoon...
Sorry if I misunderstand ports- can't you just use a smaller port area, decreasing the length, and increasing the air velocity? Is there reason to avoid that, since you don't mind noise/listen at casual volume?
a 1” wide port? a port that long & narrow is just asking for trouble. i’d look long and hard at things like port velocity and delay before i built it.
That's basically the plan. After doing some simulations, I ended up with the following design:
275145

Since the port is quite tall (11.2") and long, I think it is a good idea to brace it by dividing it into 2 slimmer ports along all of the perimeter. Each of them will be 5.3" x 0.9". This way the box is roughly 0.85 sq.ft, tuned to 27.5Hz.

SPL responce (blue - optimal quasi-butterworth):
275143


Port air velocity @ 200W:

275144


Any thoughts about the design?

As I like PRs... this a somewhat difficult thread to look at.
I bet that my attempts to squeeze the port option to the limit must be some kind of torture for you. Who knows, maybe it will sound like crap and you will get your way (PR).
:)
 

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I bet that my attempts to squeeze the port option to the limit must be some kind of torture for you. Who knows, maybe it will sound like crap and you will get your way (PR).
:)
No, I am not tortured..

PRs are designed to address volume limitations and port noise concerns.
I gave you the info so that you could determine whether they suited your goals, so I have done what I have expected someone to have done for me.

Wishing you all the best on your box.
 
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Discussion Starter #27
No, I am not tortured..

PRs are designed to address volume limitations and port noise concerns.
I gave you the info so that you could determine whether they suited your goals, so I have done what I have expected someone to have done for me.

Wishing you all the best on your box.
I appreciate it.
 

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I copied a design from a vet on here, JayinMI i think is his tag. Here's a link:
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Their woofer boxes always sound the best.🐕
 
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