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Sundown SA 12d2 box help!!!


darksoul989

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Hello everyone, I am in major need of understanding port measurements for slot ports with 3 common walls.

I have built a few amazing sounding boxes in past and always guessed port length and got lucky considering I don't know anything about the math used to figure out ports. 

I have a Sundown SA 12d2 on a Sundown 1100.5 it is @1ohm and currently in a prefab box that sounds horrible. 

I am wanting to build a box between 2-2.5sqft as I've heard these subs actually need bigger than recommended. 

I'd like to tune between 27-33hz and require a solid bottom note and a flat curve that doesn't drop till well in the 100hz range. 

Width has to be 35" max and no less than 34" heigth max of 15" and max depth 16" 

Sub and port both face rear of trunk. 

I have both BassBox 6 Pro and Torres Tuning Calculator. 

Any help figuring out a box that hits the deep lows and has a strong full range will be considered. Also help understanding how to get the port measured and cut correctly. 

Any help understanding port ratio greatly appreciated as BassBox Pro always seems to give better designs with small width ports where as Torres I find bigger ports do better. 

Thank you for any and all help to tho that post suggestions!

 

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Sundown has box specs and measurements listed on their site that are fairly decent. 


You will need to download Google Sketch to view them but its free: https://www.sketchup.com/download

Here is the design file download: http://sundownaudio.com/misc/Boxes/SA-SD-E boxes/Sundown 1-12.skp 

As for Torres if your going to use that, click the HELP button on the bottom of the program, it will explain everything your asking.

                                                      Box Frequency Tuning Calculator - FAQ/Tip Guide
                                            *------------------------------------------------------------------------------------------------*

1 - First and foremost, the RE calculator is *not* spot on, and is limited in design, so no, it will not match this calculator.

2 - When doing an oddly shaped box such as a fiberglass box, or you know the volume of a certain box you have in mind 
     that you want to build, put the net volume in the 'Desired Net Volume' box. This will bypass all dimensions entered 
     preventing you from having to guess dimensions to get a certain net volume and will allow you to tinker with different 
     port sizes and tuning. So if you know you want a box with 4 cubic feet of net volume, enter '4' into that box and it 
     will allow you to adjust tuning accordingly to that specific volume. Keep in mind that any displacement nor port volume 
     is NOT subtracted from this total. Any number in this box will override any number in the 'Desired Gross Volume' box.

3 - The 'Desired Gross Volume' box acts much like the 'Desired Net Volume' box, except all displacements are taken into 
     effect.

4 - If the '# of ports' box is greater than 0, that will automatically get taken into effect and the calculator will ignore the 
     dimensions for slot ports.

5 - The '# of Common Port Walls' box refers to how many sides of the box are going to act as sides of the port. This is 
     done by looking at the port head on and counting how many sides of the box that face of the port uses as the port
     walls. The port inside the box has nothing to do with the common port walls. Please refer to the links below for 
     examples. 

6 - Aero ports have a defaulted thickness of 3/16" -- couldn't decide whether to use 1/8" or 1/4" so I went in the middle.

7 - Port length uses the box wall or baffle(s) as part of the port length. So a port that is 10" long with one baffle using .75"
     wood will only need to be 9.25" long since the box wall or baffle(s) will account for the other .75". If using two baffles,
     then it would be 8.5" long as the baffle will account for 1.5" of port length and so on.

8 - When using multiple ports, whether they be round or rectangular ports, the port length MUST be the same for each 
     port. The port length does **NOT** get divided among the ports. This will affect your net volume and severely 
     raise your tuning.

9 - Program resolution is set to 850 pixels in width and 730 pixels in height. Try to stay within this resolution for custom
     backgrounds or program may lag. Using .png files will also help prevent program lag.
     
10 - The extra baffle box should only have a value if you plan on using multiple baffles. Leave blank or a zero if you are 
     only going to use a single baffle.

11 - Regular square/rectangle boxes do not need any numbers entered into the 'Height 2' or 'Depth 2' boxes. 

12 - Pressing 'Enter' will prompt the program to print.

13 - PLEASE NOTE: 'Physical port length' refers to the length of the wood itself needed to build the port. This is NOT the 
     same as the effective port, or the port you entered into the port length box that the box will 'see'. You measure 
     on the inside of the port (against the port wall) to measure the physical port, in the same way you measure down 
     the middle of the port to get your actual, or effective, port length.

14 - When doing an external port, the full length of the port must be entered into the port length box. Then the length of
     the external port in the 'External Port' box. This way the proper port length (the Port Length box) will be used for
     the equation, and the proper volume will be added to the net volume (the volume of the external section of the port)
     for proper tuning.

15 - On the cut sheets of boxes with different depths and heights, you'll notice 'H1' or 'D2' next to the measurements. 
     These represent which dimension is which. Here are two pictures to illustrate:
     
     Box with one height, but two different depths: http://img59.imageshack.us/img59/8449/angledcutsheet1.png

     Box with two heights and two different depths: http://img163.imageshack.us/img163/607/angledcutsheet2.png

                                            *------------------------------------------------------------------------------------------------*

--Here is the formula the calculator uses (the same one displayed in the program itself):
  http://img713.imageshack.us/img713/2590/tuningformula.jpg

--The following are links that illustrate how each ported box is taken into effect in the calculator (sub and port position can    be upwards with the same effect):

1 - Port with 0 common walls:
http://img855.imageshack.us/img855/6474/independentport.jpg

2 - Slot port with 1 common wall:
http://img341.imageshack.us/img341/9939/bottomportbox.jpg

3 - Slot port with 2 common walls:
http://img94.imageshack.us/img94/2017/middleportbox.jpg

4 - Slot port with 3 common walls:
http://img246.yfrog.com/img246/6968/slotportbox.jpg

--The images were made with Google Sketchup. Free to download: http://sketchup.google.com/

 

 

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21 hours ago, DiBo said:

I suggest 1.8-2ft³ with a tuning of 34hz. You don't need to make your box any bigger. I've ran a single sa12 and 2xSA12's... They like 1.8-2ft³. I can design you a box that'd be perfect for that woofer. 

id like a box right around 2ft³ as smaller than that im having port fart issues, but i haven't had a box yet with a port over 1.5" wide. mostly just tried sub in tons of premade boxes that iv had sitting around. need a spl/sq design thatll hit lower numbers. i know the sub can do so as seen people put them in nearly 3ft³ of box at 27-28hz and even feed them dam near double what they supposedly built for lol. 

I know for fact sub performs way better in larger box than Sundown recommends. 

my largest issue as stated is needing box to be 13.5-14" height and atleast 27 wide or more as its having amp mounted behind it via a custom rack that'll absorb vibration from the box. this is due to trunk space in my car being a hatch! only one direction i can fit amp and sadly cant mount it to seats ether due to its size as well wiring length not being enough to place it anywhere else. 

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15 minutes ago, DiBo said:

14x26.5x18

Port 12.5x2.5x30

2ft³@ 33 or add 2” to depth and get 2.4 @ 31

got one box ima try which is 14x30x15.5 port 12.5x2.5x38 @ 31 

neighbors old box for a different sub with similar specs. claims it was getting a +2.3db @ 28-30hz, +2.7db @32-33hz and had a +0.97-1.5db curve all way till 120hz before the drop off. 

ima try my sub in it and if dont like way it sounds ima sit down mess with few the programs i got to find best performance tune and go from there.

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22 hours ago, audiofanaticz said:

Sundown has box specs and measurements listed on their site that are fairly decent. 


You will need to download Google Sketch to view them but its free: https://www.sketchup.com/download

Here is the design file download: http://sundownaudio.com/misc/Boxes/SA-SD-E boxes/Sundown 1-12.skp 

As for Torres if your going to use that, click the HELP button on the bottom of the program, it will explain everything your asking.

 

seen that and dont have room for box with a 20 height or depth. actual question is how to do you cut correct measurement for port that ends up being L or T line as far as length 

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