so i made a new box today...

[kwitcherbichin 10+ year member]

its louder but not tuned too what i wanted it too be. its a lil higher then what i wanted so what do i do without makin a whole new box. could i just be able too add onto the exsisting port and it would be ok or what.

need advise

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[supermaxx123 10+ year member]

you could add it on the outside. How do you know it's tuned higher, whats it tuned to now and what did you want?

 

[supermaxx123 10+ year member]

I'd advise you to post box pics and specs.

 

[kwitcherbichin 10+ year member]

I'd advise you to post box pics and specs.

didnt take any build pics cause i sold my camera

17 high 36 wide 23 deep port is 3 high 13 wide and 20 deep

says it should be around 26 but it doesnt sound anything like the osb box. it doesnt sound nearly as low as the osb box so what did i do wrrong

 

[AudioDave]

17 high 36 wide 23 deep is a 6.6CF box (assuming you used 3/4)

and port is 3 high 13 wide using the CF on Subwoofer Enclosure Calculators, Fraction to Decimal, Parallel, Series, Port Length and Volume Calculators

says it should be 18.4" to get 26hz or thereabouts

 

[T3mpest 10+ year member]

port too small. 3x13 is tiny. That's about half the port area that you actually need.

 

[kwitcherbichin 10+ year member]

17 high 36 wide 23 deep is a 6.6CF box (assuming you used 3/4)and port is 3 high 13 wide using the CF on Subwoofer Enclosure Calculators, Fraction to Decimal, Parallel, Series, Port Length and Volume Calculators

says it should be 18.4" to get 26hz or thereabouts

which one should be 18.4 the 20 on the port?

 

[kwitcherbichin 10+ year member]

port too small. 3x13 is tiny. That's about half the port area that you actually need.

well its in a tiny car. not much i could do

 

[T3mpest 10+ year member]

You might have actually had better lowend by using a bigger port tuned higher. Trying to cram a 25hz tuning with no space to do it just leads to alot of port compression. Instead of rolling off below tuning your port just compresses and stops giving you extra ouput anywhere. You really need at least 60sq inches of port. Subs need 2.5-3 cubes a piece. Whatever that leaves you for port length is pretty much all you got. Putting the box facing towards the trunk lid, very close to the hatch will drop tuning some. You could also add a little bit of polyfill if that doesn't get it low enough. But the issue on this box is inadequate port area. You could also use areo ports next time, they save you some room too.

 

[kwitcherbichin 10+ year member]

You might have actually had better lowend by using a bigger port tuned higher. Trying to cram a 25hz tuning with no space to do it just leads to alot of port compression. Instead of rolling off below tuning your port just compresses and stops giving you extra ouput anywhere.

well **** that sucks ...

the box i had before had rediculous lows. this box and the other is basically the same same sized port and the only diff between the 2 is that the other osb box was 19 high instead of 17

 

[subzero 5,000+ posts]

Assuming you have a 15 and you want it to get low, here is what I came up with using your calculations...

If you build a slot port on the side at 2.5 inches wide and 32long you get about 20hz tuning. You can manipulate the port and get more port area. Use the RE Enclosure Calculator to find what you want. It seems that if you want lower and louder, your going to need a bigger box, a thin and long port to get the air flow needed to make that sub happy. I made a boxfor my 12's a while back tuned to 26.5 and it got low. I miss that box.

Edit: I was slow. same deal about the port. he needz mo flow

 

[T3mpest 10+ year member]

that meant your port was 2inches taller too wasn't it? This box is for 2 15's right? Anyway if you can download some tones mess with it. Play tones up high at like 40hz and notice how things get louder as the volume goes up. Then try some tones alot closer or at tuning. You'll probably find that those tones dont' scale up as nicely and at a certain point, much earlier than up higher, they begin to simply not increase in volume as quickly. That's because at tuning the subs arent' providing any output, the port is doing most of the work. A little 3x15inch port trying to move enough air to make a 25hz tone loud isn't going to cut it. As you go down in frequency you need to move more air to keep the same SPL. That means that to get high SPL's at tuning, especially down low, you need a big *** port. Try at least a 4.5" port next time using your old height. Design the box backwards. Shoot for giving 2 15's about 2.5 cubes net. That'll be 5 cubes. That leaves you with a 1.5 cubic foot port. That ends up being 28 inches of length if you make it 4.5wide at 17.5 tall (19inch tall box) That'll be around 34hz tuning. Put it close to the hatch and it'll go lower, probably 32-30hz tuning. It wont' compress as much though so you'll probably get more output overall, especially in the lower 30's late twenties, which is as low as almost anything goes anyway, even the c+s stuff is like 25 at the lowest usually. IF you can invert mount the subs, that'll give you a few more inches to add lol.

 

[kwitcherbichin 10+ year member]

You might have actually had better lowend by using a bigger port tuned higher. Trying to cram a 25hz tuning with no space to do it just leads to alot of port compression. Instead of rolling off below tuning your port just compresses and stops giving you extra ouput anywhere. You really need at least 60sq inches of port. Subs need 2.5-3 cubes a piece. Whatever that leaves you for port length is pretty much all you got. Putting the box facing towards the trunk lid, very close to the hatch will drop tuning some. You could also add a little bit of polyfill if that doesn't get it low enough. But the issue on this box is inadequate port area. You could also use areo ports next time, they save you some room too.

well i got time so thats not an issue. how do u configure how much sq inches of port i have. and each sub needs atleast 60?

 

[subzero 5,000+ posts]

How many subs are you pushing in this box and what size?????

 

[subzero 5,000+ posts]

You know with his situation, might be louder just to go with one sub. I think he implied that he is pushing two 15's