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Discussion Starter #1
Sub is Idmax 12 d2 v3
Running 425w @ 4 ohms

So my max space is 32 width x 16 height x 11 depth

I plan on making box B in the ID manual which is 2.55 or so gross volume.

Port is listed at 4" PVC x 15"

As you can see I am going to have a problem firing the port on the same plane as the subwoofer.

Q1: Doesnt a 4" pvc port seem a bit small for a subwoofer with 2" of excursion?
Q2: Should I be firing the port out the side, or use elbows to fire on the same plane as the subwoofer, and if so,
Q3: Is there a correct way to calculate elbow port area?

Thank you!
 

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Q1: Doesnt a 4" pvc port seem a bit small for a subwoofer with 2" of excursion?
Q2: Should I be firing the port out the side, or use elbows to fire on the same plane as the subwoofer, and if so,
Q3: Is there a correct way to calculate elbow port area?

Thank you!
1.no it seems fine.

2.side firing is probably going to be no problem.

3.id *guess* the corner is equal to about 2.3 inch of straight pipe, there might be a calc for it but a guess is prolly close enough....



thas how i roll.
 

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12-16 square inches of port per cubic foot of net volume is a rule of thumb, but modeling the system that gives you port velocity is the correct way to find your answer.

I'd say a 4" port is to small

I have only used WINISD, it's free, a couple of times. Try it for yourself. I have BBP6 and prefer it.

I assume you mean calculate elbow length, short side(inside diameter) + long side(outside diameter) divided by 2 will give you the middle(mean) diameter.
 

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Discussion Starter #4
12-16 square inches of port per cubic foot of net volume is a rule of thumb, but modeling the system that gives you port velocity is the correct way to find your answer.

I'd say a 4" port is to small

I have only used WINISD, it's free, a couple of times. Try it for yourself. I have BBP6 and prefer it.

I assume you mean calculate elbow length, short side(inside diameter) + long side(outside diameter) divided by 2 will give you the middle(mean) diameter.
Curious why you think ID would list it as the recommended port? I am not being sarcastic but serious I don't understand.
 

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let me ask you a couple of questions. what type of music do you listen to? what type of response are you lookin from the sub. and wats the rest of ur system consist of
 

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Discussion Starter #6
let me ask you a couple of questions. what type of music do you listen to? what type of response are you lookin from the sub. and wats the rest of ur system consist of
Essentially no Rap or Hip-Hop (only people in my car would chose that).

50% Metal
25% Alternative Rock
15% Pop/Vocal
5% Techno/Electronic
5% Classical

System is X995 H/U, Energy 6.5 woofers, Vifa Xt25 tweets, passive crossovers at 3.2khz, each side getting 145 RMS.

Remade a new box slot with slot port. 28hz before sub displacement, 2.3cuft, 22 or so square inches of port area.
 

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A 4" port is going to barely get you there port velocity-wise

a 5"ID is a safer bet. 6" if you plan on adding more power in the future.

Edit: Pffft!! Didn't read your whole last post!! See the new box design. Nice!
 

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Discussion Starter #8
A 4" port is going to barely get you there port velocity-wise

a 5"ID is a safer bet. 6" if you plan on adding more power in the future.

Edit: Pffft!! Didn't read your whole last post!! See the new box design. Nice!
Wish me luck. I called lowes, HD, etc they all say 1/8th error. So I called a building supplies place, supposedly they do precision cutting. Well see how it turns it out - so far away from my and I am sure the wood is going to be more expensive.
 

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seriously? you think ID would put the wrong box specs up for their driver??

id trust the company that built the driver over random internet box-builders.(lots of people claim to be really great at car audio, but many of these people never actually have a working system in their cars, and if they do, it often sounds like azz)

i built jls recc ported box for my 12w6v2 recently, the port is 1.5" wide!!!!! (which most www car audio peeps would say wont work)

sounds and performs awesome.

if you want your sub to perform well on everything build the recc box.

if you want to take a chance build a different one.


you going to take a saw to your tires to get more grip because www peeps say the company made the treads wrong???
 

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a 4" round port will work fine with the max don't doubt the spec sheet. for your music type any particular reason why your going with ported? sounds to me a sealed box would be better suited.
 

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go to the local hardware store and just get you some pvc elbows lol
 

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seriously? you think ID would put the wrong box specs up for their driver??

id trust the company that built the driver over random internet box-builders.(lots of people claim to be really great at car audio, but many of these people never actually have a working system in their cars, and if they do, it often sounds like azz)

i built jls recc ported box for my 12w6v2 recently, the port is 1.5" wide!!!!! (which most www car audio peeps would say wont work)

sounds and performs awesome.

if you want your sub to perform well on everything build the recc box.

if you want to take a chance build a different one.


you going to take a saw to your tires to get more grip because www peeps say the company made the treads wrong???
I stated to model it. Did I not?
I stated I thought a 4" was small, I didn't say I knew from experience that it was too small.

Please read what I typed, don't infer as to what you thought I meant.

I prefer to go little bigger on port size and be safe, not small and have to rebuild it. Model it and see what the port velocity is, it could be fine. Don't just do it because someone says it will work. That's the message I'm trying to convey.

I don't mean to come off as an ass, but how should I have taken what you stated above.
If no offense was implied and this wasn't directed at me, fine. We're good.
 

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Discussion Starter #15
Box is done. Got it done at Rona, a couple sides slightly off, added some RTV to the inside joints to seal it, turned out well though (my first slot ported box).

Not much if any port noise at full tilt.

I don't know how much the cone can move, but it is getting 600w and I had it cranked, sounded clean.
 

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Box is done. Got it done at Rona, a couple sides slightly off, added some RTV to the inside joints to seal it, turned out well though (my first slot ported box).

Not much if any port noise at full tilt.

I don't know how much the cone can move, but it is getting 600w and I had it cranked, sounded clean.
how did you calc the slot?
 
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