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How Much Port Area for Team Fi 15


cubs_fan0718

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As the title states what would be the optimal port area for 1 Team Fi 15? I was thinking between 14-16 but im not really sure. If it matters mostly for daily but I will be competing with it also.

TDHRIP_zps8bedfde5.jpg

06 Impala SS
Kenwood Excelon DDX593

Ampere Audio 150.4

Ampere Audio 5K
1 XS D4700 (front)
Mechman 320a Alt. w/ Big 3

Lots of Second Skin Damplifier

Under Construction for 2017

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You shouldnt go with the # of in^2 per cube, that is more of a rule of thumb and with that nice of a sub I'd wait to figure out an ideal box design. Not just a rule of thumb.

Hopefully someone can come in and comment on how many in^2 of port is recommended for that particular sub. I'd guess about the same as an sp4 so around 60in^2 but maybe blfok4* can chime in since he seems to have a lot of knowledge about fi/aa subs and box design.

I've gotten a blowjob and picked up my iphone behind her back to see what email notification I got from smd before

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Port area should be based off of the driver(s) in use, tuned frequency, and the xmax of said drivers. At certain area's you can only the air moving up to a certain velocity before it starts to negatively affect your output, driver, and response. Once you go over said maximum velocity you encounter those problems. This is called port compression.

After you start getting close enough to the amount of area you need flares become a good factor to work with as well, port flares allow a controlled change in velocity as air exits a port. This can prevent turbulence in the boundary layer, close to the port wall, from becoming audible. As the airspeed is lifted a little further, turbulence within the straight section of the port becomes an issue.

Let's use this graph as an example, it shows how with a higher diameter you get a higher usable port velocity and then shows how different flare radii affect it as well.

Useablevelocityat30hz_zps8d4a571e.png

The red numbers just mean that you can't get any higher velocity from that diameter no matter how much larger you make the flare radius.

As for how much port area for a single 15" Team Fi, you can't get a recommendation until you decide a frequency to be tuned at.

b_350_20_692108_381007_FFFFFF_000000.png

Krakin's Home Dipole Project

http://www.stevemeadedesigns.com/board/topic/186153-krakins-dipole-project-new-reciever-in-rockford-science/#entry2772370

Krakin, are you some sort of mad scientist?

I would have replied earlier, but I was measuring the output of my amp with a yardstick . . .

What you hear is not the air pressure variation in itself

but what has drawn your attention

in the two streams of superimposed air pressure variations at your eardrums

An acoustic event has dimensions of Time, Tone, Loudness and Space

Everyone learns to render the 3-dimensional localization of sound based on the individual shape of their ears,

thus no formula can achieve a definite effect for every listener.

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Im shooting for a 32hz frequency.

TDHRIP_zps8bedfde5.jpg

06 Impala SS
Kenwood Excelon DDX593

Ampere Audio 150.4

Ampere Audio 5K
1 XS D4700 (front)
Mechman 320a Alt. w/ Big 3

Lots of Second Skin Damplifier

Under Construction for 2017

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A good quick calculator that gets pretty much as close as needed is here:

http://www.carstereo.com/help/Articles.cfm?id=31

But if you prefer doing the math yourself you can get them here:

http://www.carstereo.com/help/Articles.cfm?id=21

http://www.diysubwoofers.org/misc/portcal.htm

Doing port calculation with this "simple" equations can only get you within +10% of the minimum port area with a well rounded flare. The only way that is sensible to figure out the absolute best is to do testing with multiple enclosures.

And of course you can get much much more complicated, but it is not really necessary for the average person building/designing enclosures.

b_350_20_692108_381007_FFFFFF_000000.png

Krakin's Home Dipole Project

http://www.stevemeadedesigns.com/board/topic/186153-krakins-dipole-project-new-reciever-in-rockford-science/#entry2772370

Krakin, are you some sort of mad scientist?

I would have replied earlier, but I was measuring the output of my amp with a yardstick . . .

What you hear is not the air pressure variation in itself

but what has drawn your attention

in the two streams of superimposed air pressure variations at your eardrums

An acoustic event has dimensions of Time, Tone, Loudness and Space

Everyone learns to render the 3-dimensional localization of sound based on the individual shape of their ears,

thus no formula can achieve a definite effect for every listener.

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thanks, I will check into those sites you have suggested.

TDHRIP_zps8bedfde5.jpg

06 Impala SS
Kenwood Excelon DDX593

Ampere Audio 150.4

Ampere Audio 5K
1 XS D4700 (front)
Mechman 320a Alt. w/ Big 3

Lots of Second Skin Damplifier

Under Construction for 2017

Link to comment
Share on other sites

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