Building Sub Box need HELP PLEASE!

Duplicate threads combined; redundant images resized.

How long does the port need to be?  It depends.  What frequency do you want to tune your enclosure to?

Did you determine that 16.5 square inches of port is enough to keep the chuffing to a minimum?  How did you determine the enclosure size?  Finally, the pictures look like the sub is sitting in a vehicle.  Did you happen to check out the name of this site?

-Robert

Hello, Chase.

You need this program: WinISD by Linear Team.
It's free (officially still "beta"), it's very good and it's relatively simple to use.
(It may take a few days to study it intensely!)

I have been using it a long time (and I have been making a small contribution to it even, many years ago, just look carefully at the "Hall of Fame" tab under "info"!  )

However, you need to know a vew properties of your speaker(s), figures known as the Thiele/Small parameters of the driver.

If you don't, the drivers may be in the extensive database of the program (although the database is a bit European minded).
Or else your supplier/manufacturer may come up with those numbers.

Good luck!


Cees

Don't play your sub now!!!!!!!  If you used 3/4" material, then your port is 3/4" long which means your enclosure is tuned to 75.5 hz.  That's way too high.  That's way too high for car audio.  That's way too high for SPL competitions.  When you play material through your sub that is below the turning frequency of your enclosure, then the driver acts like there isn't even a box.  There's no air cushion behind it and the cone moves freely.  I've modled some Kicker subs like this and it take 20 watts of power to push them to their mechanical limits.

Cees' suggestion of WinISD is great if you know what you are doing with it.  I like to use Unibox for my sub calculations.  But again, if you don't know what you are doing, then the results mean nothing.  For home theater use, I consider 25hz the highest I would tune a sub box.  That means you need a port that is 34.19 inches long.

What you really want to do is start over.  First, what are your goals?  Loud, chest thumping bass for music.  A low end monster for home theater.  A compromise between the two.  What amp are you using?  Are you willing to use a different driver?  If so, do you have a budget?

-Robert

I would only tune to 37 hz (it is spelled hertz after Heinrich Hertz) if I were making a sub for a rock music only system.  Heck some of the rap now days dips below that.  Any time you play material below your sub's tuning frequency (commonly noted as Fb) then your driver unloads.  It only takes a few watts to completely destroy your driver.  There are some drivers that can handle many hundred (some up to 1,000) watts of power in free-air, that Kicker definitely can't.

If you are short on funds, seal up the port and run a sealed sub until you can properly rebuild.

-Robert

Intense bass - It sounds like you used the car audio recommendations when building the boxes.  These recommendations don't work in a theater unless your theater is the size of a phone booth.  They take advantage of the natural gain of the small cabin of a car.  A room is larger and therefore has little to no extra gain down low.  You have to rely on the sub and enclosure only for bass.  DIY sub builders build large, efficient subs.  It is covered better under Hoffman's Iron Law - http://ldsg.snippets.org/appdx-a.php#HOFFMAN

Overlapping frequencies - That doesn't matter.  In fact, you want them to overlap because that is how you get louder bass.  You don't want the subs out of phase.  I think that was the term you were going for.  You make sure that doesn't happen by properly wiring up the drivers to be both electircally and acoustically in phase.  Since the 15 is sealed, you need to seal the others.  Ported subs are naturally out of phase when compared to a sealed sub.  A good guideline is to not mix sealed and ported subs.

aut - spelled 'ought'.  If you want my help, you have to deal with the corrections.  I'm not perfect either but being married to an English major for 17 years has helped.

pounding at 37 hz - If you look at the graph of the frequency response of a ported sub, you will see the that the driver has a similar roll-off of a sealed sub.  But as the graph of the driver drops, the graph of the port increases until it reaches a peak at the Fb.  Below Fb, the sound output for both the driver and port drop like a rock.  How will your sub sound?  I don't know.  You need to model it in one of the software applications mentioned earlier or you need to post the Theile/Small parameters of the driver.

spamming - Again, wrong term.  Spamming is if you are selling something.  You sound like a beginnerin the DIY sub world and need information.  I built my first sub in 1986 and have been hooked ever since.  I'm glad to help as long as you are open to my advice.

car amps - You mention them.  Are you planning on running car amps in the home theater?  Bad, very bad idea.  By the time you buy a proper AC to DC coverter you could have purchased a home theater amp.

-Robert

Don't worry about the spelling thing.  Sometimes I use that as well as the grammer to determine my audience.  Am I dealing with a 14 year old kid who thinks he knows everything or someone who is open to new ideas.  It sounds like you are the latter.

I'm glad you have decided to sell.  I hate to make any negative remarks about other's equipment but Kicker is crap.  Yes, they were top of the line at one time but they haven't made any real progress in years.  They are living off their reputation.

Since you have stated your goals, let me give you an idea of what you need to work with in terms of budget and size.  The Exodus Audio Maelstron-X will give you the gut wrenching bass you want - http://www.diycable.com/main/product_info.php?products_id=681&Cid=0a8a2864ebab0388087a64e23dbf5fc1 .  Check out the applications PDF in that link.  The largest sealed box would be great paired with an EP-2500 powering it - http://pro-audio.musiciansfriend.com/product/Behringer-EuroPower-EP2500-Power-Amp?sku=480697 .

-Robert