Northern Auto Tech - ECU and Blue & Me Repairs

cant get my ported box right!

Currently reading:
cant get my ported box right!

M

MartZ0r

Grease Monkey!
Joined
Oct 24, 2008
Messages
189
Points
47
hey guys

i finished building my ported box the weekend, its 2cu'ft running a 12" pioneer W308D2. the problem is the fact it doesn't seem to have as much bass force as my sealed box did. my sealed box could make the rear wings belly out!. i Must be doing something wrong, or maybe have an air leak?

Port is tuned to 34-35Hz with a 3" port. "net" volume is about 2.08 cu'ft. i was hoping to get more of a punch than my sealed, im not sure where to go from here.
 
Sealed for punch, ported for low end boom.

Let me put my beer down and ill do the math. can you give me dims of the enclosure?
 
Last edited:
hey dude.

i was always under the impression ported had more of a "kick" so to speak. i was after the feeling where you can feel the bass in your chest and outside the car. i guess i got it wrong haha

its a wedge shape, but with a top if you get me.

Height - 17"
depth 1 (top) - 15.25"
depth 2 (base) - 22"
width - 15.75"

sub Displacement 0.076ft squared.
port area 7.069
port length 5.5"
 
Last edited:
actually, i think i might what is up with it. i never accounted the air space for the wadding. il remove it and see. god knows how i will calculate that!
 
Is that 1" thick MDF.

Why do you want to hear it outside the car? So every chav can here it and then nick it. The aim of the game is to keep it inside.

How have you made the port. Can you make it again longer. You can never expect to get it right first time unless you really know what you are doing. I would say make it again and play with a few different lengths to see what your taste is.

You dont mean punch you mean boom. Punch is a kick you are talking about low end boom that takes your breath away. Unfortunately you just wont achieve that with such a sub. How much power are you giving it?
 
MartZ0r said:
actually, i think i might what is up with it. i never accounted the air space for the wadding. il remove it and see. god knows how i will calculate that!
Click to expand...

Wadding? Why do you need wadding. Is it not all shooting out of the box lol. Having it there at all can contribute to your problems. (y)
 
volxstu said:
Is that 1" thick MDF.

Why do you want to hear it outside the car? So every chav can here it and then nick it. The aim of the game is to keep it inside.

How have you made the port. Can you make it again longer. You can never expect to get it right first time unless you really know what you are doing. I would say make it again and play with a few different lengths to see what your taste is.

You dont mean punch you mean boom. Punch is a kick you are talking about low end boom that takes your breath away. Unfortunately you just wont achieve that with such a sub. How much power are you giving it?
Click to expand...


well, ya know what i mean :D i cant make it bigger, i can buy a few ports and cut different lengths. i could really do with turning it to the car couldn't i. il have to do some reading into it. not a hell of alot because i seem to be getting alot of venting noise but i think that's the wadding. (200w rms).
 
You need more power dude. You may be struggling for excursion to fill that great big box.

Get rid of the wadding that might help.

Try different port lengths

Have you flared the port? If not heat the top up really well till its malleable and then push it over a bowl or something to round it off. (y)
That should stop the chuffing.

Dont try and use too much science. Its all about trial and error. But my main point is you need more power, say 600 watts and find somebody with a scope to check your not sending a clipped signal or its by by sub.
 
volxstu said:
You need more power dude. You may be struggling for excursion to fill that great big box.

Get rid of the wadding that might help.

Try different port lengths

Have you flared the port? If not heat the top up really well till its malleable and then push it over a bowl or something to round it off. (y)
That should stop the chuffing.

Dont try and use too much science. Its all about trial and error. But my main point is you need more power, say 600 watts and find somebody with a scope to check your not sending a clipped signal or its by by sub.
Click to expand...

cheers for the advice, i removed the wadding. i used this amp on my sealed, but again as you say, different box design so different power needs. thanks for pointing that out!

the port is only flared on the outside. i will flare the inside too! i could do with an adjustable port really..
 
right, tested without the wadding, definitly sounds "better" however the hissing from the port is horrible on songs with a bit of cone movement. i removed the port and the sound went away and the sub sounded a lot better, obviously it cant be used like that though. so is this down to the fact the turbulence on the port?

i can make a video if you would like to hear it for yourself.
 
Yeah it's called port velocity. Is the port loose at all or have any gaps at all
as this will cause chuffing.

How long would a 4" port have to be. You will get less noise with more port area.

I try to build ports that are removable so I can try a few different lengths.
 
i made the ports removable but really tight. i cant see any gaps. 4 inch diametter would be about 9-10 inches. other option is adding another 3 inch.
 
volxstu said:
If you can get another 3" then that would be good but what is wrong with a 10" length?
Click to expand...

i probably could fit one, but i dont know of any ports that are that long unless i use standard pvc pipe, witch i have got (4 inch). id rather have something thats already flared, maybe you could suggest something?
 
iv added another 3 inch port and also got another spare port. i must admit, its done the trick! bass is amazing and there is no distortion or chuffing, even under high excursion. i haven't tuned it yet because i want to get more ports so i can cut a few and try them one after the other. its currently sitting at about 35Hz. i need a bigger amp now because undrr high volume its clipping the sub. got my eye on a alpine mrp 1000 in a few weeks.

thanks stu!
 
You must log in or register to reply here.

Similar threads

J4MALD1N
Punto Evo Punto Evo Subwoofer not right
Replies
1
Views
876
J4MALD1N
J4MALD1N
R
Panda Stereo getting hot - issue? (2008 Panda Dynamic Eco)
Replies
3
Views
459
koalar
koalar
Jodsclass
500 Struggling to get an update for 7" Uconnect
2
Replies
36
Views
8K
RALA0
R
vidtek
Fitting aftermarket Head Unit to 2011 Panda Mylife
Replies
0
Views
115
vidtek
vidtek
Vitalii
500 Hi,everyone I have a problem, the radio in my Fiat 500 does not work and she told me that the radio is locked. Accordingly, it doesn’t work for me,
Replies
1
Views
666
varesecrazy
V
Back
Top