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So, I lack the technical know-how required to make a traditional ported enclosure... Anyway, do port tubes act the same way as built in ports?

According to my IDQ spec sheet, If I make a sealed enclosure at around 3.8 cubic feet, and I use a port tube that is 4" by 13.8", I'll have a tune of 28hz.

Is it really as easy as building a sealed box, cutting a port hole and sticking a port tube in? Do I need to worry about where I place the tube?

I was quoted $250, and I would like to save $200 by doing it myself. Will my approach work?
 

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I am interested in an answer here too. I am about to build my first ported box and would prefer to do it right as well the first time.
 

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Yes it really is that easy. Use tubes that have Flared ends and your good to go.
 

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lol, yes, it is really that easy. the design phase of a ported box is the hard part. in general it is best to try to keep the port facing the same direction as the sub, but not required.

buy this and you are done:

Precision Port 4" Flared Port Tube Kit 268-352
 

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Yes it really is that easy. Use tubes that have Flared ends and your good to go.
yes, you need the falred ends or you'll have more port noise!!!!!
 

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Not to hijack, but how do you deal with bends in port tubes? ie if you had to front-port a long, shallow enclosure?
you can get tube elbows or if you are building a slot port, you just make your bends around the inside of the box. as stated above. you just have to make sure that you calculate your port volume and subtract it from box volume. I have seen boxes with ports that make 3 turns and wrapped around nearly the entire box to get the length needed.
 

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This is all great info! Thanks guys. I have a few additional questions if you don't mind.

1. Are there any specific recommended port diameter sizes? 2", 3", 4"?
2. Does port placement on the box face matter?
ex: Mounting a 90degree elbow port next to the driver?

Thanks in Adv!
 

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This is all great info! Thanks guys. I have a few additional questions if you don't mind.

1. Are there any specific recommended port diameter sizes? 2", 3", 4"?
what you want to keep in mind is port area and port velocity.
too little port area and you will have a high port velocity. that can cause port noise, which is annoying as well as port compression which can cause the tuned freq to change.
just remember that every time you double port area you will double port length
diameter doesnt make much difference as you can use multiple ports to tune it.
2. Does port placement on the box face matter?
ex: Mounting a 90degree elbow port next to the driver?

Thanks in Adv!
doesnt make much difference. just make sure you dont get the ports too close too the woofer, you have to brace them somehow. ;)
 

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Actually ive got a few questions people can hopefully answer.

1. Is the port volume (Vp) calculated into the volume of the box (Vb)?

ex. is Total Volume = Vp + Vb or is Vb = Vp + (Remaining Volume)


2. Most of my box calculations end up with boxes around 9.5 L but with a port length of between 30 and 40 in. This is assuming a square port of 9.5 in (length of side of box) X .75 in. Does this seem reasonable to people?

3. What exactly does the tuning frequency entail? I always feel its where you get the max efficiency (max SPL vs. lowest energy requires).

4. Should i just say f the ported box and make a t-line? What would be the benefit of this?
 
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