Thoughts on my design?

[Braindead]

I just designed a box for 2 ab xd 10's. I'm aiming for 2.5 cubes @35Hz.

My port dimensions are 2 wide*12.5 high*17.5 deep

View attachment 26544631

Do my calculations match up, and will there be port noise?

Click to read more...

 

[AndrewHD 10+ year member]

This box only has around 2.2 cu ft internal (when using 3/4" material) not including port displacement

 

[Milk Mayne 10+ year member]

I'd suggest a little more port area as well.

 

[Braindead]

I'd suggest a little more port area as well.

Could I just widen up the port to about 4 inches and increase the depth to about 15in, or would that do all kinds of crazy **** to my tuning

 

[bbeljefe]

If that 25" measurement isn't the full width, like it looks, then you're just under 2.3 cubes before driver displacement. You have 25in² of port, which is a bit too little. You should have about 16in² per foot on that power with those drivers.

If those drivers displace about .10ft then you're at 2.1 cubes and with that port your tuning is ~40.

And yes, you can make the port wider and add depth to the box in order to accomplish your desired volume and tuning. Just remember to subtract port and driver displacements from your gross volume.

 

[AndrewHD 10+ year member]

I think you should make the box a bit bigger (deeper to be exact) and then widen up that port to about 2.75-3"

 

[Nutdawg651]

If that 25" measurement isn't the full width, like it looks, then you're just under 2.3 cubes before driver displacement. You have 25in² of port, which is a bit too little. You should have about 16in² per foot on that power with those drivers.
If those drivers displace about .10ft then you're at 2.1 cubes and with that port your tuning is ~40.

And yes, you can make the port wider and add depth to the box in order to accomplish your desired volume and tuning. Just remember to subtract port and driver displacements from your gross volume.

Did u get my pm

 

[bbeljefe]

Just got it man...

 

[Braindead]

If that 25" measurement isn't the full width, like it looks, then you're just under 2.3 cubes before driver displacement. You have 25in² of port, which is a bit too little. You should have about 16in² per foot on that power with those drivers.
If those drivers displace about .10ft then you're at 2.1 cubes and with that port your tuning is ~40.

And yes, you can make the port wider and add depth to the box in order to accomplish your desired volume and tuning. Just remember to subtract port and driver displacements from your gross volume.

Whenever I put my desired measurements into winISD (2.5 cubes, 33Hz, 12.5*4 port) I end up with a port length thats around 40in. Am I doing something wrong?

 

[Braindead]

Also the 25" is the full width, I'm not sure why I didn't put the line to the end.

 

[Braindead]

AB doesn't list the displacement on their website, would .1ft^3 be a good estimate?

 

[bbeljefe]

Also the 25" is the full width, I'm not sure why I didn't put the line to the end.

Oh, well then your box is way too small. And WinISD is telling you to make the port that long because of the area of the port. Less area will net you a shorter port and more area, a longer one. And if you're using WinISD Beta, pay close attention to the vent mach. I don't know why it's not on the newer versions, because it tells you whether or not the port area you've chosen will result in a noisy port.

You'd probably be safe with a 2.5-3" wide port in that application. That would cut the length down to around ~24".

 

[Braindead]

Oh, well then your box is way too small. And WinISD is telling you to make the port that long because of the area of the port. Less area will net you a shorter port and more area, a longer one. And if you're using WinISD Beta, pay close attention to the vent mach. I don't know why it's not on the newer versions, because it tells you whether or not the port area you've chosen will result in a noisy port.
You'd probably be safe with a 2.5-3" wide port in that application. That would cut the length down to around ~24".

I'm using the alpha version. So should I just maintain the port width and have it bend around the corners until i reach the correct port length?

Plugging in the dimensions (14H*25W*18D giving me around 2.8 gross) and using .2 as a rough estimate for driver displacement, and a port thats 12.5*3*27.25 I'm getting around 43.7Hz tuning. Makes no sense, I have to be plugging in the wrong number somewhere

 

[bbeljefe]

I'm using the alpha version. So should I just maintain the port width and have it bend around the corners until i reach the correct port length?
Plugging in the dimensions (14H*25W*18D giving me around 2.8 gross) and using .2 as a rough estimate for driver displacement, and a port thats 12.5*3*27.25 I'm getting around 43.7Hz tuning. Makes no sense, I have to be plugging in the wrong number somewhere

Yeah, that's 2.8 cubes, but your port volume and your driver displacement reduce that volume. Figure the port at 3.75*12.5*23.25 for a volume of 1090in² plus 346in² for driver displacement and add that to your existing depth measurement. You need to add 4.88" to the depth.... or, about 5 inches and your port length for 35 Hz will be 23.25.

 

[Braindead]

Yeah, that's 2.8 cubes, but your port volume and your driver displacement reduce that volume. Figure the port at 3.75*12.5*23.25 for a volume of 1090in² plus 346in² for driver displacement and add that to your existing depth measurement. You need to add 4.88" to the depth.... or, about 5 inches and your port length for 35 Hz will be 23.25.

So in order to reach my desired tuning have all the dimensions basically the same and have a port thats 3.75*12.5*23.25? In order to do that would I need to have the inner part of the port go 13.5in deep then have the port continue at a right angle 9 more inches, giving me a port thats 3.75*12.5*23.25? Also that'd put me around 2.5 net cubes, right? Also thanks for all the help man