Is this even considderred a port? Need sub placement help aswell *PICS*

[WOT]

Just redisgning my box for a higher tune for some more output and to get some of my trunk back. The box is for 2 15's single chamber ported

DJ originally gave me some box plans to give me a 40hz tune, but I said I still wanted this to beat to metal and rock and he said ok maybe a 36hz tune would be better.

The ORIGINAL port is in red, then when he said a 36hz tune might be better, he said to butt the 2 green pieces to the OUTSIDE of the port and to the side and made it sound like this would act as an extension of my port. Now its the weekend and I havent heard back from him but I wanna finish the box tonight.

Do you guys think that was pictured is a correct way to lengthen a port?

ALSO, I dont know where to place the subs. Im doing sub up port back. My subs are 15" and the port is 5.75" wide (7.25" including wood width) and my box is only 37" wide on the OUTSIDE, so 35.5" inside. Doesnt give me much room....

What im curious about is where I should place them on the box

Away from the port towards the front of the car

Cose to the port towards the rear of the car

Middle of the box

Actually now that I think about it, I may only be able to put the subs at the back clostest to the rear of the car with that 2" addition I think would get in the way.... Or maybe I could always just extend my port LONGER into the box...?

Im curious as to why DJ said to place the extra 2" of port outwards like that.

thanks

Click to read more...

 

[Supergumby5000 5,000+ posts]

whoever told you to do that is an idiot.

 

[CJL 10+ year member]

im sure he knows what hes doing

 

[Pioneer~Saturn 5,000+ posts]

He said to do this because (i hope) the port is the port's width away from the back of the enclosure and shouldnt be closer...exteending it on each side is the way to do this maintain that same distance away from the back wall of the enclosure and now the back wall is part of the port too

 

[CJL 10+ year member]

He said to do this because (i hope) the port is the port's width away from the back of the enclosure and shouldnt be closer...exteending it on each side is the way to do this maintain that same distance away from the back wall of the enclosure and now the back wall is part of the port too

exactly //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif

 

[Supergumby5000 5,000+ posts]

He said to do this because (i hope) the port is the port's width away from the back of the enclosure and shouldnt be closer...exteending it on each side is the way to do this maintain that same distance away from the back wall of the enclosure and now the back wall is part of the port too

if you look at the numbers, its not even close hehe

what you need to do is make your port longer, but thats not hte correct way to do it

 

[Pioneer~Saturn 5,000+ posts]

^well assuming its made of .75" thick mdf/material...

24-(1.5 +16)=6.5 inches away from back of box...

so what you should really do is extend you port back 3/4" and then add around 1.25" on each side...but in all reality doing it like the drawing will get you almost the same result

 

[WOT]

Well yeah thats what I was thinking that maybe he wanted to keep the port ending from the back of the box. Specifically what he said was for the tune that I desired, I was to make the port 20" long from the front of the box, so it would be going 19.25" into my box, only leaving 4" to the back wall. I dont mind just making it the straight 20" if it wont make a difference.

Kinda confused on why a 20" straight port would give the same tune as a 16" deep port with 2" angles, wouldnt that only be like 18"?

 

[arizona 10+ year member]

the other two inches are on the back wall

 

[WOT]

Just to add, this is what his original msg was, I dont think he did the math when he said I should place the box in the center of the box (because its impossible with a 37" width and those wings on the port end, I think)

"You could lengthen the port to 20" measured from the outside face of the box, that would tune you down to about 36-37hz which will hammer the lows. Make your port 16" deep measured from the outside face of the box and add 2" at right angles to the end of each port wall. This will give you an effective port length of 20". The subs will play down into the mid-upper 20hz range in this box. There is no music below these frequencies; what little there is you wouldn't be able to hear it anyway."

So I was hoping I could just extend the port to make a straight 20"er or if someone oculd help me get a way to make this work.

 

[audioholic 5,000+ posts]

If you "T" the port out as you show in the pic, each arm of the T will need to be half the total port area of the single large original port. If you make each arm of the T the same cross sectional size as the original port, you have now doubled your 'port area' for a portion of the port's length, and thrown tuning right out the window.

 

[WOT]

Ok so I just want to make a straight port then, to avoid any of this. How far away can I bring the port to the back wall and not affect tuning? Id like to get as close to the 20" depth as possible to bring the tune into the high 30's

Thanks alot

 

[WOT]

bumpbs is! im ready to cut this!!!

 

[WOT]

Oh, so you mean he wants me to basically just make the port huge to get that 20" length and lose alot of box volume? Wouldnt it be better if I just made the port 18" deep straight into the box, and Id just get a tune of 37-38hz and have that exact minimum of distance away from the enclosure wall.... that sounds like the best alternative, just make it 18" deep into the box from the box face and then Id put the subs, firing upwards, in the dead center front to back of the box....

 

[bass-aholic 10+ year member]

what the fuck happened to your old box? Did you ever try switching the phase on one of your amps before you go out and build another whole box?