Ported box in small space???

[microhaxo 10+ year member]

My friend has a 350z and he is just not satisfied with the current output if a Fi Q in a 1.3cuft box, i have seen boxes made for trucks that are ported, he is really interested in making a ported box, is this possible with the small amount of space to work with?

Whats the smallest the box can be to be ported and sound good?

tuning would be about 32hz..

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[thegreatestpenn 5,000+ posts]

transmission line box time

 

[microhaxo 10+ year member]

what is that?

 

[azimuth 5,000+ posts]

what is that?

transmission line. small space and transmission line usually don't go together. is this a 10 or a 12?

 

[microhaxo 10+ year member]

12" I think the max he can make a box is about 2.2 ft cubed..

its a 350z and on the back latch it says it can store 2 golf bags, LOL

Basically i have a Phoenix Gold RSDC 12" in a 2.75 cuft ported box getting ~800 true watts rms but tuned at 1200w rms via 50hz -3db tone from a hifonics 1606d and mine takes your breath away, his doesn't sound nearly as good, he has a Fi Q and same amp feeding it a little more power but it just doesn't hit NEARLY as loud in his sealed 1.3cuft box.

 

[fasfocus00 5,000+ posts]

if his box is currently sealed, i'd try adding poly fill before building another box.

i'd probably go with 2 8s ported instead of a 12. a smaller woofer in a proper enclosure will always sound better than a larger woofer in an enclosure that is not sufficient for it's needs.

 

[microhaxo 10+ year member]

well he already has a big amount of cash invested in that fiQ and it says its made for ~1.3cuft sealed but it sounds lack luster for the price.. Poly fill doesn't seem to change anything output wise.

Also his is open cab, it should be way louder than mine, im in a sedan.

 

[fasfocus00 5,000+ posts]

well he already has a big amount of cash invested in that fiQ and it says its made for ~1.3cuft sealed but it sounds lack luster for the price.. Poly fill doesn't seem to change anything output wise.
Also his is open cab, it should be way louder than mine, im in a sedan.

i'm not gonna go into the science of how polyfill works but it does help with output. not sure if you stated but what kind of power does he have on it?

 

[azimuth 5,000+ posts]

well he already has a big amount of cash invested in that fiQ and it says its made for ~1.3cuft sealed but it sounds lack luster for the price.. Poly fill doesn't seem to change anything output wise.
Also his is open cab, it should be way louder than mine, im in a sedan.

2 cubes ported should do the trick. i'm actually kinda surprised that 1.3 sealed doesn't do well with the Q. from what i've heard, they do well in a sealed box.

 

[microhaxo 10+ year member]

When I say well, (as well as my friend) we are comparing it to my RSDC and previous subs, the Fi Q was supposed to be high quality and way better than type r's and i assumed better than my RSDC. But right now it just doesn't sound all that great.

he is feeding it ~ 1400w rms via dmm

~ 900w true rms (songs arent recorded at -3db..)

Im pretty sure its the box that is limiting the output of the sub.

Theoretically shouldnt his hit harder than mine? He has an open cab small *** car with a sub getting over 1000w rms, yet mine hits twice as hard.

 

[azimuth 5,000+ posts]

When I say well, (as well as my friend) we are comparing it to my RSDC and previous subs, the Fi Q was supposed to be high quality and way better than type r's and i assumed better than my RSDC. But right now it just doesn't sound all that great.
he is feeding it ~ 1400w rms via dmm

~ 900w true rms (songs arent recorded at -3db..)

Im pretty sure its the box that is limiting the output of the sub.

i would say it's the box also. that being said, i thought the Q sounded pretty darn good sealed. i really liked it ported, in around 2 cubes, tuned low (i think 30hz was the tuning).

 

[fasfocus00 5,000+ posts]

When I say well, (as well as my friend) we are comparing it to my RSDC and previous subs, the Fi Q was supposed to be high quality and way better than type r's and i assumed better than my RSDC. But right now it just doesn't sound all that great.
he is feeding it ~ 1400w rms via dmm

~ 900w true rms (songs arent recorded at -3db..)

Im pretty sure its the box that is limiting the output of the sub.

Theoretically shouldnt his hit harder than mine? He has an open cab small *** car with a sub getting over 1000w rms, yet mine hits twice as hard.

that seems to be more than enough power for that sub regardless of the enclosure. I would say if you have a pillow (polyfilled not down feathers), i'd stuff the box loosly and see what happens. if it doesn't help, check your box for any leaks. than if the polyfill doesn't help and the box has no leaks. build a ported enclosure with an aero port.

 

[microhaxo 10+ year member]

He wants to do an aero port, but the calculator on here: http://www.psp-inc.com/ isnt making much sense to me.. If we have a 2.0 cuft box and we want it tuned to 29hz and the diameter of the pvc is to be 3" i need over 20" of PVC?!?!? but if i make the diameter 1" i only need 1.79 " like how does that work?

I am confused :|

Are those calculators on crack or what?

 

[fasfocus00 5,000+ posts]

He wants to do an aero port, but the calculator on here: http://www.psp-inc.com/ isnt making much sense to me.. If we have a 2.0 cuft box and we want it tuned to 29hz and the diameter of the pvc is to be 3" i need over 20" of PVC?!?!? but if i make the diameter 1" i only need 1.79 " like how does that work?
I am confused :|

air speed would be an explanation. it's alot more indepth than that. you can read up on this on your own. i'd keep the tune closer to 32hz.

 

[microhaxo 10+ year member]

so then why when i try to calculate the length of the tubes do i get crazy numbers like 131" like i cant do that shit..

to have this even work i need to have

for 32hz at 2.0 cuft what should the length of the port be if i want a 4" port?

the calculator says 13.61 inches but that means i would have to angle the tube because i dont have that amount of depth to work with.