How do you pick port area?

[Exaran]

I've looked around, and found all kinds of equations and calculators for determining the length of a port based on box volume, tuning frequency, and port cross-sectional area...

How do you know how much cross-sectional area you need? Or do you just make it as big as you can fit?

This will be for an SQ oriented daily driver

[Norcalracer283]

BBP

10 chars

[Exaran]

?? Que ??

What you talkin about, willis?

[jellyfish420]

power?driver?

[Exaran]

Its for an RE8, at 200W RMS. I kinda wanted to know how i would go about figuring it out for any sub tho too

[jellyfish420]

i was always told same area as the driver.

[Exaran]

wow, that sounds pretty big for a .5 cube box

[jellyfish420]

i think the re8 is .5sealed and 1ft ported. correct me if i'm wrong.

[Exaran]

.21 sealed .5 ported at 32hz from their site

After fiddling with WinISD I came up with .5-.6 ported at 28hz for some good low end

I think the RE10 is .5 sealed 1.0 ported....

[audioholic]

i was always told same area as the driver.

That cannot be right. If that were the case, the proper port area for a 15in driver would be 175 sqin. Way way too big.

Check with the driver manufacturer for their recommended port area.

[DBfan187]

^^^I think that only applies for SPL only installs?

[OLD_SCHOOL]

spl guys say use at least the sd on a driver... for a 15xxx thats like 125 in^2 seems a little much for a non comp box.

use a modling program and check the vent velocity at your power

[BASS OUTLAW]

i thought that the air velocity in the vent should not exceed 10% , of the velocity of sound in air, thats why u go for more cross sectional area, to avoid whistling.
didnt knew it got SPL issues

[jellyfish420]

WIth SPL, enclosure design plays a huge role (not just volume/port area/tuning)

like what???

[req]

i thought it needed an 8:1 ratio...

so what if you dont have BBP or winISD... where can i get one of these.. id really like to use them.



/offtopic
nice warning label jellyman =D