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Blown JL12W6

My new ported box for my Fi Q12 2 Cubic Ft. @ 33 HZ

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I finally picked up the pre cut pieces of the box I designed using the RE enclosure calculator, but I would like to verify which port length will be ideal for tuning the 2.0 Cubic ft. box between 30-33 HZ? I know the RE calculator is not really accurate so, here's my box measurements:

Width = 23"

Depth = 15"

Height = 15"

Volume = 2.0 Cubic ft.

Port width = 1.5"

Here's the pic of the box. The length of the port inside the L shape port is what I would like to verify.

e1e1fff2.jpg

Now, should I go with 12" or 5" port length? The default RE calculator gave me a tuning freq of 33 HZ using 5" port lenth but it is not accurate. I'll be building the box sometime this weekend so before I put everything together, I would like you enclosure experts to pick the best port length that will be suitable between 30-33 HZ.

Thanks.

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I'd go wider on the port width. Try to keep width to height ratios greater than 1:9. And just using WINISD with 1.5" width and 15" height for the port, the length needs to be about 15" long for 32hz tuning in a 2.0 cuft NET box. And 22.50 in^2 port area is kinda small IMO.

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Good thing I have a few small pieces so I can change the port length and 12.5" lenght of port would be good enough. I can't change the 1.5" port width because it will mess up the other measurments.

Thanks.

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Hate to break it to you but the box is to small. After port and driver displacement your looking at 1.65ft^3.

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Yeah, I didn't look at the dimensions and just thought he knew about NET volume. Start a new box if your box is going to be too small. Its going to be way peaky and sound like shit.

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Can I just decrease the port width and tuned higher like 34-37HZ by going with 3"-5" port width? I don't wanna take too much space in my trunk but I would be happy if I can tune this box between 34-37 Hz.

Thanks

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You mean height? Because you can't decrease port width from 1.5" to 3-4. You should have gone with aeroport. Get a 4" aeroport and you may have enough room in that box. I wouldn't go out of Fi's recommendations.

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Yes, I mean the port lenght, sorry this is my first box build. Is the 5" port lenght too small and can damage the sub if the box can be tuned between 35-37hz?

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You're going to pop spiders and stuff tuning that high..because you need to tune your subsonic filter 2-3Hz below the port tuning frequency..so you're going to miss out a ton of the low end tuning that high..

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What? I asked if you mean height then you say yes but go to say port length? You need to get a 4" aeroport and redo the front baffle.

You cannot have a 5" port length with the same port area if you want to be tuned anywhere in the 30s or even the 40s. You're going to tune that box in the 60s.

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The SQUARE PORT WIDTH of 1.5" that I can't do anything and it will stay the same. The half piece of the "L" shape port which is called SQUARE PORT LENGHT is what I was trying to reduce to either 5" or stay with 15" and make room for extra volume at the same time balancing the tuned frequency.

Anyways, Im thinking or either going for Aeroport design or suck it all up and change my dimension to 16" Depth and keep the 23" width just to make room for volume. Any other practical suggestions?

Thanks

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