what size port?
Printed From: the12volt.com
Forum Name: Fiberglass, Fabrication, and Interiors
Forum Discription: Fiberglass Kick Panels, Subwoofer Enclosures, Plexiglas, Fabrics, Materials, Finishes, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=30224
Printed Date: May 31, 2024 at 9:43 PM
Topic: what size port?
Posted By: aem7506
Subject: what size port?
Date Posted: April 12, 2004 at 7:46 AM
ok im going to use to 12" rockford fosgate HE svc 8ohm speakers. i want to put them in a slot ported box. i got room for a 36 x 14 x 24. question is can some one calculate me a slot port for that. im just gettin new to the hole porteed thing and i wnat to gve it a try and i heard ported is my best bet. also can i get some help on placement were to put the port thanks ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Replies:
Posted By: kickerstang
Date Posted: April 12, 2004 at 3:49 PM
if i was you i would do to seperate chambers and do a round port in each one measuring 3" x 8", that would tune it to around 26Hz which is very very loud. place the ports in the front bottom corners of the box. this is a set up for street beat, the lower you tune it the louder it sounds. it won't do great on the meter but it'll sound loud as fu@k. i assume the measurements you gave were outside dimensions and you are going to use 3/4" MDF which gives you an total internal volume of 5.6ft3 and 2.8ft3 per sub. ------------- what!?!?! you want some??
Posted By: aem7506
Date Posted: April 12, 2004 at 7:17 PM
well i was planning on seperating them anyway but u really think tube is better than slot ive heard slot is the best......... ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: cmh
Date Posted: April 12, 2004 at 7:40 PM
Kickerstang is right... almost , a port is a port as long as it is tuned properly. Go out surfing and download a free version ou WIN ISP it is a box building program in which you can actually see what any woofer/box combo will sound like. It also does all the calcs for you, even port tuning of "slotted" or round ports. And as for tuning it lower to be louder, that really depends on the driver, using winisp you can see a defined PEAK at or just after the tuning frequency of the port and about 3-6 DB roll off at frequencies above that, bue 12 - 19 db roll off before that. Also www.partsexpress.com has really nice flared round ports of all sizes for less than 3$ each and they are professional looking. Just keep in mind the 3 inch rule... Ports must be at least 3 inches from any side of the box or woofer. This will reduce standing internal waves and cancelation. Also a port can be placed on any side of the box you want as long as it is not obstructed by a wall in the car, apply that 3 inch rule to the outside as well.
Posted By: cmh
Date Posted: April 12, 2004 at 7:55 PM
PS-
take it from me I built a 1.8ft3 2 chamber box for my 2 12" volfenhag zx-4712dxv subs. I ported it to tune at 45hz (ports on the sides) and I can get 100 average DB in the cab. I peaked out at 119db at 48hz (I got less DB above and below the tuning Fz) with all configured to 1 4ohm load with 1000 watts. My moral is that I origionally put them in a box (the same box) with a tuned port of 25HZ and couldn't break 88-94 DB. So it is woofer theil small parimeters and a good box building calculator that will give you the most out of each spacific driver.
Posted By: kickerstang
Date Posted: April 13, 2004 at 11:07 AM
i did a 147 with to kicker comp vr 10's in a box tuned to 36Hz. i've never heard of anyone tuning a box that high except big time SPL competitors and they usually tune around 52-55 but that's just to burp it. for a stereo that you drive around and listen to you would have no low bass it would all be high tight punchy bass ------------- what!?!?! you want some??
Posted By: pspadotto
Date Posted: April 13, 2004 at 11:44 AM
Go out surfing and download a free version ou WIN ISP it is a box building program in which you can actually see what any woofer/box combo will sound like. I did a quick google search for win isp...couldn't find it. Anyone have a link to where to download it?
Posted By: pspadotto
Date Posted: April 13, 2004 at 11:47 AM
Sorry, my previous post should have looked like this: pspadotto wrote:
Go out surfing and download a free version ou WIN ISP it is a box building program in which you can actually see what any woofer/box combo will sound like.
I did a quick google search for win isp...couldn't find it. Anyone have a link to where to download it?
Posted By: aem7506
Date Posted: April 13, 2004 at 6:24 PM
well all these nubers and i sti aint got a clue whati should do should i use the 3 x 8 port that will tune ti at 26 hz ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: kickerstang
Date Posted: April 14, 2004 at 12:09 PM
yeah, that will bang it a$$ off, you'll be turning heads everywhere, everyone will think you've got two 15's or more back there ------------- what!?!?! you want some??
Posted By: audiomechanic
Date Posted: April 14, 2004 at 6:01 PM
it also depends on if the speakers and port are loading of of something. you typically get more output if they are.
one option you can do is make an opening as wide and tall as you can, then make different length ports that will fit in that opening. that way you can change it around til you get it to sound the way you want.
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Posted By: dangerranger96
Date Posted: April 14, 2004 at 6:49 PM
Your subs will play better, longer, cleaner, and louder if you go with a little bit smaller box roughly 36" x 14" x 18" using 3/4" mdf. Using that box, i would tune it down to 29hz, which would mean using a 3" x 8 3/4" port. You would have to split the box in two with a sealed brace if you want the port to be tuned correctly. If you want tighter, more punchy bass, then you should reduce the size of your box.
Posted By: aem7506
Date Posted: April 14, 2004 at 8:05 PM
well ive already stasrted making the box in shop class i got a 36 x 22 x 15.5 ... and almost done so what port can i do with what i got and make it slami want loud noticable bass ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: dangerranger96
Date Posted: April 14, 2004 at 8:38 PM
if you made it a 2 chambered box, use a 3" wide x 6.5" long port for each chamber If you made it a single chamber, use a 3" wide x 2.5" long port
Posted By: aem7506
Date Posted: April 14, 2004 at 8:45 PM
ok i want to get as much as possible out of these 2 twelve thats the goal so sshould i make it shorter.... one single chamber or two seperate chambers tell me what u think i should use ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: dangerranger96
Date Posted: April 14, 2004 at 8:55 PM
if you can put a piece in the center of the box to make it two seperate chambers, i would. This leaves you some insurance incase you blow one of your subs, or if it becomes disconnected, the box wont have the wrong airspace for the working woofer. you can go ahead and leave the box like it is and just put that piece in. putting that piece in will also help to stop the box from flexing, which makes the subs quieter, and can damage them. one thing to make sure to do is to seal up all of the corners of the box. Silicon caulk works well, just make sure to let it cure before you put your subs in the box, that way it doesnt mess up the woofer or surround.
Posted By: aem7506
Date Posted: April 14, 2004 at 9:01 PM
well if u think its worth it i havent really started putting it together yet so if it will be louder 18 inches long i will d that. also i was planning on dividing it i have made plenty of speaker boxes im jsut new to the ported stuff so if i make it 18 instead of 22 what port size do i need to make this thing slam...... sry for buggin u i just want to make sure ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: dangerranger96
Date Posted: April 14, 2004 at 9:11 PM
dont worry about it Go with the box size being 36" x 15.5" x 18". Put a piece of mdf in the center of the box to seperate it into 2 chambers. Use 2 ports, 3 inch diameter, 8 3/4 inches long, by the way, what amp are you putting these on
Posted By: aem7506
Date Posted: April 14, 2004 at 9:14 PM
i have a 900 watt rockfordfosgate would thos work ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: dangerranger96
Date Posted: April 14, 2004 at 9:17 PM
it will work real nice. just make sure that you dont blow the amp when you wire them up
Posted By: cmh
Date Posted: April 14, 2004 at 11:27 PM
Sorry, I tried to reply last night and was unable to sign in, I mispelled look for Win ISD you'll find it at :
https://www.linearteam.dk/
Also I like the idea of a 3" pore made long then you cut it down 1/2 inch at a time till you get the sound "YOU" want. After all that is all that matters! Oh, and make the dual chamber!
I am a professional audio engineer of 10+ years out of Las vegas, I know LOUD personally! CHeck out our company www.avvegas.com and enjoy the looks you get as you go boom!
Posted By: aem7506
Date Posted: April 16, 2004 at 11:59 AM
where should i put the subs should i put them on the 15.5 x 18 side but then i would have a problem with getting the ports 3 inches away from each wall or should i put them on the 18 x 36 side???????
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<<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: dangerranger96
Date Posted: April 16, 2004 at 8:41 PM
you want the subs to face the rear of the vehicle your puttin them in, so if that is the 18 x 36 do that
Posted By: aem7506
Date Posted: April 16, 2004 at 9:55 PM
sh*t i didnt knwo u want them to face the rear whys is this its going ina hatchback by the way ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: cmh
Date Posted: April 17, 2004 at 12:18 AM
Well it has been proven that rear facing the subs will increase the SPL in any cab trunk or hatchback. As for the ports any side or the top is fine. If it is impossible to stay 3 inches away just try your best to keep away from the sides the most. Think of water as you throw a stone into a calm surface, notice the round ripples. They are perfectly round untill they hit a reed growing out of the water and that distortion sends ripples back at the original perfectly round rippled in turn distorting them. The sound waves are similar and as the port moves closer to a wall the distorted waves are promenant at the port wher as further away from a wall the pure waves exit the port prior to being hit from the distorted waves comming from the wall called STANDING WAVES. I hope you were able to follow all that.
Posted By: dangerranger96
Date Posted: April 17, 2004 at 12:27 AM
exactly as he stated
Posted By: aem7506
Date Posted: April 20, 2004 at 7:24 AM
aight i finsihed the construction of the box try it out and its just what i wanted. i appreciate all the help but i got another question........... i have 2 kickerr cvrs 12's dvc 4ohm subd in a 2.2 each sealed chamber box well its not giving me what i want so kickers website says that 2.25 is for deep bass well it only shows for a slot port and i wanted to drop in a round port since the box was already made and fits nice can any one caclulate what size port ill need thanks ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: cmh
Date Posted: April 23, 2004 at 12:29 AM
Use that Win ISD I told ya bout....
Posted By: aem7506
Date Posted: April 23, 2004 at 10:35 AM
i got the program vbut i dont know how to use the damn thing ------------- <<98 Mercury Mountaineer>>
"Sound"
Pioneer DEH7300
Pioneer 5/7 (4)
12'Kicker compvr (2)
900 Rockford Fosgate Amp (2)
Posted By: dangerranger96
Date Posted: April 23, 2004 at 4:45 PM
i dont know a whole lot a bout that program either, im glad you like the way the box plays
Posted By: audiomechanic
Date Posted: April 25, 2004 at 12:13 PM
what are the dimentions of the port that they tell you to use? just post is here and myself or somone can convert it for ya
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