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View Full Version : two ports instead of one?



ndnbolla
05-16-2005, 02:08 PM
would it make a difference if two smaller ports were used rather than one full sized one.

i am asking this because I would like to go with that clean symmetrical look if you catch my drift, one port on each side.

jujumantb
05-16-2005, 02:09 PM
No difference, make sure you calculate the lengths out correctly though!

DFW40
05-16-2005, 02:22 PM
I was like you and liked the dual look vs the one port look. But I had much more port noise with two instead of 1. I had dual 3 inch pvc ports and went to a single 4 inch port which was actually 2 inches less of port area but it had zero port noise. For example (4) 2 inch ports is roughly the same as 1 single 4 inch port but the (4) 2 inch ports have more port noise because there is alot more surface area on the port walls with the (4) 2inch ports to slow down the velocity of the air. It has to do with the ratio of air vs. port surface area.

ndnbolla
05-16-2005, 02:51 PM
I dont want to sacrifice anything in doing this so I guess no dual ports for me.

If I ported a 12W6v2 and tuned it low (27-30hz) would it sound almost as good sealed SQ wise. Obviously sealed has better SQ but should I sacrifice a little bit SQvand go ported. That way I get louder while still maintaining SQ.

DFW40
05-16-2005, 03:40 PM
I would go with a single 4 inch pvc port tuned to around 27 hz like you said and it will sound great and still get pretty darn loud.

req
05-16-2005, 04:13 PM
sealed will sound way better than ported. ported will get louder.

id stay away from anything lower than 4" IMO. but thats me.

DFW40
05-16-2005, 04:22 PM
everyone has been slamming ported the last few days
the new forum boners will now be

1. upgraded front stage with emphasis on the mid-bass
2. old (class A/B) amps that are 22 inches long
3. sealed boxes

Raven
05-16-2005, 05:06 PM
Jmac your avatar rocks.

bcarpenterfhl
05-16-2005, 07:06 PM
keep it sealed...

otherwise, JL recommends atleast 18.75 square inches for port area.

ndnbolla
05-16-2005, 07:30 PM
okay... now I think I will go sealed.

Now, JL recommends anywhere between .9 cu. ft. to 1.5 cu. ft.

What differences in sound and loudness will I hear as the internal volume would get bigger from .9 to 1.5?

On another note, who would consider this an upgrade from two 2004 12" Type R's in a sealed enclosure. Both have 1 cu. ft. and are being powered by a nine.1 in a 2 ohm configuration.

I plan on using the nine.1 to power the JL in a 1 Ohm load.


:) Wow, I've been here for a while and now I am going back to asking newbie questions huh? Ah well. :)

joeldirt
05-17-2005, 12:30 AM
I was like you and liked the dual look vs the one port look. But I had much more port noise with two instead of 1. I had dual 3 inch pvc ports and went to a single 4 inch port which was actually 2 inches less of port area but it had zero port noise. For example (4) 2 inch ports is roughly the same as 1 single 4 inch port but the (4) 2 inch ports have more port noise because there is alot more surface area on the port walls with the (4) 2inch ports to slow down the velocity of the air. It has to do with the ratio of air vs. port surface area.


in theory... you would think that doubling the port diameter would give you the same port area..... however it is different. two two inch ports at 12" long each (this is only an example) will not give the same tuning frequency of a single 4" port at 6" length....

bcarpenterfhl
05-17-2005, 01:11 AM
ndnbolla,

the smaller the box the more mechanical power handling the sub increases and the "punchier" the bass is. bigger boxes decrease the subs mechanical power handling, and people have found the bass to be a bit "boomier". people who underpower their subs will often put their sub in a bigger enclosure because of this. IMO, the 12W6v2 sounds best with 500-600 watts in 1.25 ft.^3 box.

bcarpenterfhl
05-17-2005, 01:34 AM
and because you chose a bad *** sub:

http://img77.echo.cx/img77/4684/jl12w6v29ie.jpg
1.25 ft. ^3

ndnbolla
05-17-2005, 12:26 PM
and because you chose a bad *** sub:

http://img77.echo.cx/img77/4684/jl12w6v29ie.jpg
1.25 ft. ^3

thanks bcarpenterfhl, i didn't even ask and you made me one.

you think that maybe you could decrease the depth and height a lil bit and make it wider. so maybe the width of the box will be 1.75 times the height. i hate to be and *** and ask for a design for free like this.

Or maybe you make boxes and you would be able to make one for me? Covered with some dark grey carpeting would just about be perfect.

And of course, :greedy: :greedy: :greedy:

Decipha
05-17-2005, 12:34 PM
everyone has been slamming ported the last few days
the new forum boners will now be

1. upgraded front stage with emphasis on the mid-bass
2. old (class A/B) amps that are 22 inches long
3. sealed boxes


i thought i was the only one who realised that its nice to know others see whats going on as well maybe we can put an end to this at once

bcarpenterfhl
05-17-2005, 01:29 PM
thanks bcarpenterfhl, i didn't even ask and you made me one.

you think that maybe you could decrease the depth and height a lil bit and make it wider. so maybe the width of the box will be 1.75 times the height. i hate to be and *** and ask for a design for free like this.

Or maybe you make boxes and you would be able to make one for me? Covered with some dark grey carpeting would just about be perfect.

And of course, :greedy: :greedy: :greedy:

since its a small box, and probably not that much of a hassle to ship, i will consider making a box for $65 + shipping. i dont think i'll be able to carpet it though, i'm all out of super 77 and contact cement, however, i'll prep it real nicely, and you can do whatever you want to it once you get it. because of tipping, i wouldnt recommend decreasing the depth all that much (unless you plan on mounting it to your trunk of course).

DFW40
05-17-2005, 01:39 PM
since its a small box, and probably not that much of a hassle to ship, i will consider making a box for $65 + shipping. i dont think i'll be able to carpet it though, i'm all out of super 77 and contact cement, however, i'll prep it real nicely, and you can do whatever you want to it once you get it. because of tipping, i wouldnt recommend decreasing the depth all that much (unless you plan on mounting it to your trunk of course).

don't let him get off that easy tell him to go buy some more super77 or contact cement, carpeting is harder than box building. Give him an extra 20 and get it carpeted....or I could not stick my head in other peoples business. LOL

bcarpenterfhl
05-17-2005, 01:46 PM
don't let him get off that easy tell him to go buy some more super77 or contact cement, carpeting is harder than box building. Give him an extra 20 and get it carpeted....or I could not stick my head in other peoples business. LOL

yea shouldnt. but super 77 is like 15 bucks itself.

DFW40
05-17-2005, 01:53 PM
yea shouldnt. but super 77 is like 15 bucks itself.

I did not have the best of luck with the 77 but really like the "gel" contact cement. It takes longer but you can get it on great with a cheap paint brush. Whenever I make a box I always use it for 3 weeks or so before I carpet it because it is a pain in the arse to make it look nice.

later

ndnbolla
05-17-2005, 02:26 PM
Maybe I will leave it uncarpeted, sand it and give it a few layers of that stuff that makes the wood shiny (forget what its called).

Is there any way to make it look wider? Since you didnt say that you couldn't lessen the height maybe you could lessen the height by a couple inches and make it wider a couple inches. If it's asking too much then we can forget about this whole wide thing.

Also I will pay extra if you can do a flush mount and put a speaker terminal in the back.

joeboxer5876
05-17-2005, 02:40 PM
or send it to me and ill do a metallic plaster and clear urithane coat over it. im going to do a fiberglass box with this plaster called lusterstone (http://www.fauxfx.com/LusterStone.html)<- click here. i take pics of it. i just have to find the time to make a complicated box in a reg cab s-10

ndnbolla
05-17-2005, 02:46 PM
or send it to me and ill do a metallic plaster and clear urithane coat over it. im going to do a fiberglass box with this plaster called lusterstone (http://www.fauxfx.com/LusterStone.html)<- click here. i take pics of it. i just have to find the time to make a complicated box in a reg cab s-10

you think i can see some of those pics. and just how expensive could this be cuz I am interested in the ancient gray.

okay bcarpenterfhl, how bout these dim: W/18", H/14", D/12.75"

These are the exact dimensions that JL recommends for a sealed box.

joeboxer5876
05-17-2005, 02:54 PM
i have never done it on a box yet but i can sent you a sample of the real product done on a small piece of poster board. it would probably not be cheap but i am an office manager and have access to some products. it would probably take a quart of lusterstone and about 4 oz of sealer. a quart of ancient grey is $24.95. its not cheap but if i can get the product for free it might be worth it to you. it would take me 6 to 8 hours with dry time and it takes about 3 coats of lusterstone and 3 coats of sealer. now that i think about it, it would probably be 60 to 80 buck if i can get free product. if your still interested pmme with and address and ill send you a free sample of what that product will actually look like. or you can wait till the end of the summer and check out pics of my box.

bcarpenterfhl
05-17-2005, 06:31 PM
you think i can see some of those pics. and just how expensive could this be cuz I am interested in the ancient gray.

okay bcarpenterfhl, how bout these dim: W/18", H/14", D/12.75"

These are the exact dimensions that JL recommends for a sealed box.

i can build it to whatever specs you would like. hit me up on AIM if possible.

PS, because of the W6's rim thing, i dont think it would look very good flush mounted. but i can build it to whatever you want.

jujumantb
05-18-2005, 12:06 AM
People are sheep ...
lmao, exactly my thoughts at this point in the thread! :veryhapp:

bcarpenterfhl
05-18-2005, 12:31 AM
lmao, exactly my thoughts at this point in the thread! :veryhapp:

and you say that why?

based on your experience with the W6v2, why do you feel a sealed box isn't the best choice for this sub?