I am designing an enclosure for a Sundown Audio Z-15 (D4 wired to 2 ohms on a Sundown Audio SAZ-2000D), it will be a daily driver. I listen to a lot of chopped and screwed, r&b, old school and rap so I decided to stick with 31Hz. This may be a temporary box or a full time box depending on how it and the sub treat me. I havent build a box since August of 2008 so its been a while, my max dimensions are 16.5"H x 34"W x 21"D. Jacob told me I can make the enclosure as big as 4ft^3 and tuning anywhere from 30-35Hz and 28Hz if I wanna go lower. So right now Im sitting with a box at 3.85ft^3 @ 31hz with 60 in^2 of port area (port area range = 46-62in^2). Made of 3/4" mdf, standard slot port (l-shaped) opening.

Enclosure Dimensions

Outside = 16.5"H x 33"W x 20"D

Port = 15"H x 4"W x 29.75"D

Sub Displacement = 0.19ft^3

Physical Port Length = 15.25"

Cut-Out Baffles

Back = 33" x 15"

Front = 28.25" x 15"

Right Side = 18.5" x 15"

Left Side = 19.25" x 15"

Port 1 = 14.5" x 15"

Port 2= 7.75" x 15"

Bottom/Top = 33" x 20" (2)

Thanks for help, if there need to be any corrections than let me know I would appreciate it. I got the specs from two different box designing programs.

I am designing an enclosure for a Sundown Audio Z-15 (D4 wired to 2 ohms on a Sundown Audio SAZ-2000D), it will be a daily driver. I listen to a lot of chopped and screwed, r&b, old school and rap so I decided to stick with 31Hz. This may be a temporary box or a full time box depending on how it and the sub treat me. I havent build a box since August of 2008 so its been a while, my max dimensions are 16.5"H x 34"W x 21"D. Jacob told me I can make the enclosure as big as 4ft^3 and tuning anywhere from 30-35Hz and 28Hz if I wanna go lower. So right now Im sitting with a box at 3.85ft^3 @ 31hz with 60 in^2 of port area (port area range = 46-62in^2). Made of 3/4" mdf, standard slot port (l-shaped) opening.

Enclosure Dimensions

Outside = 16.5"H x 33"W x 20"D

Port = 15"H x 4"W x 29.75"D

Sub Displacement = 0.19ft^3

Physical Port Length = 15.25"

Cut-Out Baffles

Back = 33" x 15"

Front = 28.25" x 15"

Right Side = 18.5" x 15"

Left Side = 19.25" x 15"

Port 1 = 14.5" x 15"

Port 2= 7.75" x 15"

Bottom/Top = 33" x 20" (2)

Thanks for help, if there need to be any corrections than let me know I would appreciate it. I got the specs from two different box designing programs.

You say port is 29.75" deep, but then that the length is 15.25"... I'm confused...

If you measure from port opening to the end of the port, how long is it? 29.75 I'm guessing but I'm not sure.

And also, as far as I know you are using a double baffle for sub-side and no additional bracing, correct?

Specs seem off to me I got 3.79ft^3 @ 34hz

Specs seem off to me I got 3.79ft^3 @ 34hz

See I knew I was messing up or the enclosure program I was using wasnt right. Well Im trying to get a rear firing port and subwoofer enclosure (17"H x 33"W x 21''D=max dimensions) double baffle, between 3.75-3.85ft^3 @ 30-31z.

Ive got 3.82cu3 at a little over 33hz. This isnt accounting the driver disp though on the tuning aspects. Not sure how much the tuning will go down though.

I want it tuned a little lower, really between 30hz if you can get it accurate.

Change that port length #2 to 17" and it will be about 3.69 at 31 flat. Accounting for the same as last.

Change that port length #2 to 17" and it will be about 3.69 at 31 flat. Accounting for the same as last.

So your saying that in my cut sheets just change the port length #2 piece to 17". Does anything else need to change besides that and the volume?

Sorry bigrank916, dont mean to be difficult but let me start over so we can get this down because I want to buy the wood this weekend and get them to cut it at Home Depot. I want it to be a rear firing port and subwoofer enclosure (17"H x 33"W x 21''D=max dimensions, /75" mdf) double baffle, between 3.75-3.85ft^3 @ 31hz.

Change that port length #2 to 17" and it will be about 3.69 at 31 flat. Accounting for the same as last.

So your saying that in my cut sheets just change the port length #2 piece to 17". Does anything else need to change besides that and the volume?

Yes. If you change the port length to 17" the volume will go down as well as the tuning. Thats all you do.

Or you can max those dims out and get 3.94cu3 at 31.13hz. 33x17x21. More likely 30 something with dd.

I like that program. What is that? Nice and simple.

inside dimensions of 15x31.5x18.5 port size 15 x4 x29.75 if there is no "L" on the end it's to close to the wall. this will cause tuning issues it has to be about 27.5 inch plus the other piece that make the "L" For the port. any ways with what you did i got 3.6333 cubic feet at 31.75 hertz it a crappy design with to many flaws. i think the problem is the L and the box shape it just throwing the calculator off. i would redesign or go for bromo's box design.

I like that program. What is that? Nice and simple.

x2, is there a way I can get that program so I can play with it and make some changes.

Its an excel spreadsheet I made, sorry not for distribution.

Its an excel spreadsheet I made, sorry not for distribution.

Well not a problem at all I understand, Im gonna need for you to do a little more work and I will be done. Can we change the max dimensions depth to 20"D and lower the tuning close to 30Hz (30-30.5hz) and volume after displacement 3.6-3.8ft^3. Thanks and I promise Im stuck with these numbers I just posted.

Its an excel spreadsheet I made, sorry not for distribution.

Ever thought about distributing it at a fee anytime in the future? (just curious)

Its an excel spreadsheet I made, sorry not for distribution.

Well not a problem at all I understand, Im gonna need for you to do a little more work and I will be done. Can we change the max dimensions depth to 20"D and lower the tuning close to 30Hz (30-30.5hz) and volume after displacement 3.6-3.8ft^3. Thanks and I promise Im stuck with these numbers I just posted.

It is no problem, if you really wanted to I could do a design in sketch up and throw 45's in it and everything. But that would eat up your internal volume pretty quick.

Naw I dont need any 45's, I think a double baffle will suffice enough (I already though of doing that). So is it 3.72ft^3 @ 30.63 or 30.01hz for tuning, perfect box man I definitely appreciate it. Happy New Years to you and yours.

Its an excel spreadsheet I made, sorry not for distribution.

Ever thought about distributing it at a fee anytime in the future? (just curious)

No, not really. It has some glitches in it that need to be watched, I can fix the glitches but its something that I know is there and I rarely run into it so I never took the time to add to the formulas.

Naw I dont need any 45's, I think a double baffle will suffice enough (I already though of doing that). So is it 3.72ft^3 @ 30.63 or 30.01hz for tuning, perfect box man I definitely appreciate it. Happy New Years to you and yours.

30.01Hz that is with end correction(virtual port length). 30.63 is the tuning of the physical port length.

Yes, Merry New Year.

Just curious as to what the white blocks are in the port, if you dont want to answer I understand. But thanks a million again.

Just curious as to what the white blocks are in the port, if you dont want to answer I understand. But thanks a million again.

Just something I put there to tell me how long the port needed to be to get to that point in the enclosure.

Ok well if you ever consider selling you enclosure software keep me in mind. Thanks Again.