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Discussion Starter · #1 ·
Hi everyone,
This is my first post here so I'd like to start off by saying nice to meet you all.
I have had a sealed enclosure in my ute for a good 6 months now. I went sealed as I thought I was very constricted for size having only gone off forum research from others previously taking on the build. Upon measuring myself I have found that I can fit a much larger box and have decided to design a ported box. I have done all the calculations and the box is tuned to 30hz. I am going to be using a JL12W3V3-2 and their website states box tuning of 30hz to be ideal. Their ported box specs state a net internal volume of 1.75cuft/49.6L. I have managed to squeeze in a net volume of 1.56cuft/44.21L. Also, my port width and height is 2.36in/60mm x 5.83in/148mm. I'm just wondering whether the strange shape of the box will affect the sound too much? I have done a lot of research and a tonne of adjustment to port size and length I'd just love some feedback and a bit of info as to whether or not it is viable. I've posted pictures and thumbnails of the box below for reference. I hope to find some help :) Thanks, Andrew
60mm1.JPG 60mm2.JPG 60mm3.JPG 60mm4.JPG 60mm5.JPG
 

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Discussion Starter · #2 ·
Also please let me know if I've posted this in the wrong place and I can repost in another thread
 

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Blue is your design, red is 1.75 cu ft @ 30 hz w/ JLs recommended port area and tuning at 30hz.

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Your response is down about 1dB at 30hz which is practically inaudible. Vent speed is up a bit but I'm not sure its a big deal (this is at 500 watts btw). You could increase port area to reduce this.
 

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Discussion Starter · #4 ·
Wow Lithium you have just blown me away with your reply. Thanks heaps mate I was going to try using software but I wasn't too sure how to go about it. You've answered my question perfectly mate I appreciate that heaps. Will the decrease in net volume due to increased port area have a huge impact on sound? Sorry if I'm asking too much. Thanks
 

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Wow Lithium you have just blown me away with your reply. Thanks heaps mate I was going to try using software but I wasn't too sure how to go about it. You've answered my question perfectly mate I appreciate that heaps. Will the decrease in net volume due to increased port area have a huge impact on sound? Sorry if I'm asking too much. Thanks
It would be handy to use the plots as the answer key, if you were tempted to try and use the s/w.

Where in Au are you ?

you could omit the port and use a passsive radiator in the top, which would recover some internal volume… However in a Ute, if the idea is to throw something on the box (like a dog), then staying with your design makes more sense.
 

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Discussion Starter · #7 ·
Hi Holmz,
Thanks for your reply. I live in Adelaide mate.
Unfortunately a passive radiator won't work as the box is going next to the fuel cell which is under a steel panel. I've designed the box to be as close to this as possible at the top so there would be no room for the radiator to move. It's a bit of a tricky place for a box which is why everyone I've seen do it as well as myself has gone sealed. By moving a couple of things in this area I can fit a box of this size which allows the port as I believe the sealed design is only 1cuft if that. Not sure if the ported approach is completely viable but going off of Lithiums response it doesn't seem too far off JL specs. I'm not 100% sure what you mean by plots mate. Thanks, Andrew
 

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Discussion Starter · #8 ·
Another reason I want to go ported is I've heard the w3 sounds great in a good ported box and also I have such a heavy lack of anything 40hz and below it's not even funny
 

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ok… I’ll bite… what car is it going into with the fuel cell?
 

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Discussion Starter · #10 ·
Haha sorry it's more of a fuel tank than a cell, its just inside the chassis. It's going in a vz Ute mate
 

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To answer one of your original questions, No, this particular shape will not cause any issues with the subwoofers performance. Best of luck!
 

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Discussion Starter · #12 ·
Thank you for your reply squiers. That has eased my mind and I'm now keen as ever to get this thing built. Cheers
 

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Haha sorry it's more of a fuel tank than a cell, its just inside the chassis. It's going in a vz Ute mate
Just the use of the term hints at a muscle car.
 

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@ Gamooey - try different sw enclosure orientation,... output can drastically change with different enclosure orientation. (UP/BACK, DOWNFIRE,...)
Be careful when positioning port - make sure you have for port diameter clearance arround, in front and behind the port. If possible use aeroport endings to minimize port noise. You can also put " foam on three sides of enclosure (do not apply it to the baffle!) IF YOU ARE ORIENTED MORE TOWARD SQ THAN SPL.
 

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Discussion Starter · #17 ·
@LBaudio thanks for your reply mate. That is very helpful thank you. I will play around with it tomorrow and see how I go. The foam is a great idea. I will get back tomorrow with my findings. Already thinking about it I can squeeze in a lot more box volume by having the port exit a different side. Cheers mate
 

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Discussion Starter · #18 ·
After working out the ebp value of the sub I've decided that I'm going to build a new sealed box to suit jl's spec. Thanks for your help guys
 

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Discussion Starter · #19 ·
Actually I'm very indecisive I'm going to make both and have each for a different type of listening lol 🤷‍♂️ and hope that the ported box sounds alright
 
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