Port question 12" lvl2 (question answered)

[MrSkippyJ]

Build link in my sig if you want to see the box.

This is temporary till summer when I can rebuild box. Box was build for a 12" JL but the DC 12" is so much bigger than the JL, it won't fit.

Box will be 1.335 cubes (minus port displacement, sub will be inverted). I want a tuning of around 35hz and I think a 4" (pvc port) that is 12.5" long will do the trick. Does that sound right?

Also, if I use a heat gun and bowl to flare the ports a bit, how do you figure the flare into the port size equation. For example, how does a flare affect how you measure length or diameter of the port.

Thanks.

Edited December 19, 2010 by shkibbybop

[matt402]

u need a longer port if u want it @ 35hz. ~17.8" long.

ur port would also need to be slightly longer if u flare it (to keep the same tuning).

[MrSkippyJ]

u need a longer port if u want it @ 35hz. ~17.8" long.

ur port would also need to be slightly longer if u flare it (to keep the same tuning).

Ok that will be a bit long, so a slot port it is. I am guessing a 4"*3" slot port would need to be the same length correct? well close to the same length anyway.

Sorry, it's early and I remembered why I cannot do that right now.

I know a 3" round port is really to small, but I can flare the ends and that size port will give me the length I need. Remember, this is a temporary thing until I can build a box for the DC.

My main question with a 3" port is will it hurt the sub any doing it this way?

EDIT: I AM AN IDIOT. I can put a bend in a 4" port and all will be good...so 4"@17.8" long it is...

sorry, it is early for me.

Edited November 19, 2010 by shkibbybop

[MrSkippyJ]

u need a longer port if u want it @ 35hz. ~17.8" long.

ur port would also need to be slightly longer if u flare it (to keep the same tuning).

How do you adjust the length to compensate for the flare?

[matt402]

i had a 3" port for a 12 in 1.8 cubes, did pretty good =].

psp-inc says to add 1" longer length for a flared port.

it really depends on how big the flare is tho...

[MrSkippyJ]

i had a 3" port for a 12 in 1.8 cubes, did pretty good =].

psp-inc says to add 1" longer length for a flared port.

it really depends on how big the flare is tho...

so you think a 3"port would be fine? That sure would be easier.

[matt402]

it worked ok for me ...

[MrSkippyJ]

it worked ok for me ...

I will try that then. it's temporary, if I don't like it, I will do a 4" port. Not like I can't make the whole bigger. The whole box is getting rebuilt in the summer anyway. Thanks for all your help.

[matt402]

np

DC FTW!

[MrSkippyJ]

Fawk, this thing is starting to get broken in and GOD DAMN. The lows are getting loud and the whole thing is getting LOUDER. This is one hell of a sub, it just shit stomps that JL out of the water.

How the hell do you people do it with these big ass setups?

Anyway, thanks Rusty and DC peeps for a kick ass sub!