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If I port a box at 28hz do I still get plus 6 db all the way to 80hz?
 

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If I port a box at 28hz do I still get plus 6 db all the way to 80hz?
Let me know what you want drop1 and as soon as I find a moment I’ll model it for you. To answer your question though, no you will not realize a 6 db gain at 80 Hz if the fb is at 28 Hz compared to a sealed subwoofer.
 

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If I port a box at 28hz do I still get plus 6 db all the way to 80hz?
If it is that sort of box that you want, then it is called a bandpass.
It will be a 6th or 8th order.
 

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Drop1, what prevents you from learning how to graph this stuff on your own for analysis?
 

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Drop1, what prevents you from learning how to graph this stuff on your own for analysis?
It's a fair question. I think we're all wondering the same.


You can lead a horse to water...
.... I could probably just teach you how to use WinISD so you could run these things yourself. Same with when you asked for info on what cubic feet something is. That's just math, easy math at that. Let's just teach you how to use something like Sketchup or whatever so you're comfy with making this stuff. It can be fun too. ....
...and be completely ignored. :shrug:

:dead_horse:
 

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IDK, I personally found it a lot of fun to get decent at WinISD and Sketch
 

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IDK, I personally found it a lot of fun to get decent at WinISD and Sketch
Absolutely!

I'm not familiar with Sketch, but playing with WinISD has been a lot of fun and absolutely fundamental to what little I've managed to learn about woofer and subwoofer systems.
 

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If you are porting to 28, I doubt you'll hear any gain at all up around 80 Hz. Depending on box size and a variety of other factors, you'll usually get about one octave boosted (with a peak in the center). So tuned to 28, maybe somewhere around 20-40 Hz.
 

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If you are porting to 28, I doubt you'll hear any gain at all up around 80 Hz. Depending on box size and a variety of other factors, you'll usually get about one octave boosted (with a peak in the center). So tuned to 28, maybe somewhere around 20-40 Hz.
Or 25-40...
It drops like a rock on the low end of the port.
 

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Which is something you want to happen, because a port unloading can be a gruesome thing, at high SPL. Best to also have a standard filter there in your DSP/head unit or at least at the amp, to prevent bad things.
 

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Which is something you want to happen, because a port unloading can be a gruesome thing, at high SPL. Best to also have a standard filter there in your DSP/head unit or at least at the amp, to prevent bad things.
Even without a subsonic it will drop like a rock.
The subsonic just keeps it from destroying the subwoofer.

Drop: This is where a tunable PR allows one to adjust the tuning frequency post-facto. (Whether a 3" port is large enough for a Brahma I do not know... but you will want to know that up front)

Lanson: have you done any bandpass boxes using a PR for the lowest frequency?
 

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Lol! Mr. “PR” Holmz. :p:D

I’d be interested in hearing about some of your band passes with PRs. :)
 

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Lol! Mr. “PR” Holmz. :p:D

I’d be interested in hearing about some of your band passes with PRs. :)
Me too:)
The Haus boss has a list of other things for me...:mean:
 

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Lol! Mr. “PR” Holmz. :p:D

I’d be interested in hearing about some of your band passes with PRs. :)
I have done several 4th orders bandpass enclosures before. What benefit or change would I see using a PR vs. a traditional port with a bandpass either 4th or 6th order
 
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