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pj_chevy03
07-02-2004, 08:56 PM
1 rockford fosgate punch z 10"
box dimensions {exterior}
width...........26.5
height..........14
top depth......5.25
bottom depth.....8
rf T/S parameters
would like the box to be tuned to 33 hz.
i need the port dimensions...thanx
http://www.rockfordfosgate.com/scripts/rightnow.cfg/php.exe/enduser/fattach_get.php?p_sid=Jox2sofh&p_tbl=9&p_id=185&p_created=1065551422

bigwheel15
07-02-2004, 09:38 PM
First you need the interior dimensions, then use this (http://www.carstereo.com/help2/Articles.cfm?id=31) to find the port length.

Trixter
07-03-2004, 10:43 AM
First you need the interior dimensions, then use this (http://www.carstereo.com/help2/Articles.cfm?id=31) to find the port length.

Wow. I'm glad you found this. Since loudspeakers101.com went down I was looking for it. This calculator is accurate...a lot better than WinISD. I have done calculations that have the same outcome as this one. The only thing you need to remember when using it is that you need to do it twice. Once using the internal box volume (- sub displacement) and when you get your port length, find the port displacement, subtract that from your box volume number that you used the first time, and then do it again using the new box volume to find you final port length. It also accounts for port correction as well.

Trixter
07-03-2004, 11:02 AM
PJ: what is the driver displacement? The T/S doesn't give it. Give me the displacement, also try to figure it out. Try using a 3" port. Your box is already 0.68cu' to start out with. When you post the displacement I will do the math also. now that we have a calculator to work with it should be pretty easy to do.

pj_chevy03
07-03-2004, 02:30 PM
PJ: what is the driver displacement? The T/S doesn't give it. Give me the displacement, also try to figure it out. Try using a 3" port. Your box is already 0.68cu' to start out with. When you post the displacement I will do the math also. now that we have a calculator to work with it should be pretty easy to do.
i really have no idea on sub displacement...this box is not for me and thats all i could find on the internet on the sub...also i dont wanna use pvc when building the box i want to do the same kind of port that yall help me figure out for my 2 sonys if possible...thanx

pj_chevy03
07-03-2004, 02:36 PM
also i have no idea how to use that calculater

Trixter
07-03-2004, 03:48 PM
Well then disgrgard that last PM I sent you. I don't have time now to do the box but I will try and get back to you on it.

Trixter
07-03-2004, 03:49 PM
According to BBP6, driver displacement = 0.06 ft^3 ...

I don't use calculators, they **** me off ...

I think I like the paper and pencil way myself. I tried that calc. again and I have come to this conclusion.

pj_chevy03
07-03-2004, 09:41 PM
Well then disgrgard that last PM I sent you. I don't have time now to do the box but I will try and get back to you on it.
were you referring to me...because i have no pm from you

Trixter
07-04-2004, 10:11 AM
I meant pj, but since you didn't get nevermind disregarding it.

Use a 2" piece of pvc that is 8" long.

Or a 3" piece that is 21" long.

JimJ
07-04-2004, 04:56 PM
not a fan of PVC ports myself...too easy to get port noise unless you take a lot of precautions in routing the edges down smooth...

slot ports rule :D

pj_chevy03
07-05-2004, 12:23 AM
I meant pj, but since you didn't get nevermind disregarding it.

Use a 2" piece of pvc that is 8" long.

Or a 3" piece that is 21" long.

what about with a slore port...like with the port in the corner of the box...2 sides of the box = 2 sides of the port and 2 separate pieces of wood for the other 2 pieces of the port...i really dont wanna fool with pvc cuz i've heard of bad port noise

pj_chevy03
07-05-2004, 10:39 PM
what about with a slore port...like with the port in the corner of the box...2 sides of the box = 2 sides of the port and 2 separate pieces of wood for the other 2 pieces of the port...i really dont wanna fool with pvc cuz i've heard of bad port noise
i meant slot port... could u give me the dimensions for a port that would be coming our the top of the box in the corner of the box where 2 walls of the box make up 2 sides of the port or if that cant be done... have it where a wall only makes up one side of the port... but preferably in the corner of the box...thanx

pj_chevy03
07-06-2004, 11:05 AM
bump...........

Trixter
07-06-2004, 06:50 PM
Honestly, I don't thihnk you will have any problems with port noise because the enclosure and the port are so small. If you were to go with a slot port, you will take up more displacement, in turn making the port longer to keep the box tuned. If your set on not going with PVC port you can either go with a bigger box to accomidate a slot port or you go with a precision port. http://www.partsexpress.com/webpage.cfm?&DID=7&WebPage_ID=3

pj_chevy03
07-06-2004, 07:05 PM
i have a question...why would the port be so huge...if u remember when u did my box it was a 2.1 cu.ft. box and the port was only 2" x 4" x 6.5" for a tuning of 32... why would it not be similar in this situation as well... and also if i do have to go with pvc u dont think i would have too much port noise with a 2" pvc cuz i dont wanna have to put a bend in the pvc

pj_chevy03
07-08-2004, 07:03 PM
bump..........

Trixter
07-08-2004, 09:25 PM
It would have to be longer because the box is smaller. The smaller the box the higher the freq. The longer the port the lower the freq. So the smaller the box, the longer the port needs to be. I think a 2" port would work out ok if your not using a lot of power. Otherwise, if you worried about it, the only thing I can say is get a bigger box...but it seems that you can't so I think this is the best you have to work with.

pj_chevy03
07-09-2004, 11:20 AM
the sub will only recieve 100 watts if even that (sony amp) so it's definitely not a high powered system by any means...and also on my box (the one with the 2 sonys) u did take into mind that there would be 2 subs in one box????? i'm sure u did and i dont know if it would make a difference with port length if u had 1 sub or 2 subs but i'm jus makin sure

Trixter
07-09-2004, 01:11 PM
I would say go ahead then, since it's only 100w. If you don't like the way it sounds then try something else, but it seems kinda limited on what you can do.

Your other box, I did account for two subs.