Box too big? 2 SA12s


BassDrop69

CarAudio.com Newbie
May 4, 2019
18
0
hey guys, I have two Sundown Sa12s rev3 d4 wired to 1ohm on a Digital designs m1d in a box built by net audio. its 5.25cft air space with port tuned to 34hz. now I see sundown recommends only up to 2cft ported per sub. so is that 1.25cft over the suggested max effecting my subs performance? thanks 

 

DRBOOM

CarAudio.com Well Known
Nov 21, 2018
249
51
Hey mate,

The recommended enclosure design by the manufactures is done under the impression that it can accommodate most car trunk areas.  This provides the buyer an impression on box building options.  Now you can also build your own using WINISD amp or other box building app.

The rules of physics also come into play to so in order to tune the box low and loud, you will have to go bigger enclosure, much more then recommended.  A larger enclosure yields a lower tuning and increases bass response in the lower frequencies,  That is why you cannot compare those flat subwoofers for utes and under-seat subwoofers  to generate 'thunderous' bass, since the enclosure will now allow it!  In my opinion, they are very inefficient but some may love the little bump they get from them.

Secondly, its made by people in the know so you can be rest assured they will tune and set the gains for you to get the most out of them subwoofers! :laugh:

There are many people who just throw in a subwoofer in a prefab box to save money since they are just after a 'thump' in their system but each to their own! :rolleyes:

As long as you don't drive the subwoofers to distortion, you should be fine mate!   

 

THATpurpleKUSH

Smoke weed everyday
10+ year member
Sep 30, 2009
7,433
512
Banging gears and passing queeers
Seems like a reputable shop, I'm trusting that the box specs are indeed accurate. That being said the extra 1.25cf will make the box more efficient and maybe slightly boomier sounding. Sundown subs are overengineered and have a high mechanical excursion. Given the power level the subs will see after impedance rise you will be just fine using a box that big. 

 
Last edited by a moderator:

PPVtahoe11

CarAudio.com Enthusiast
Aug 13, 2018
99
24
I got my SA 10s in like 10cubes plus. They love it. Broke my Chevy emblem off the back of my truck the other day and I only got 500watts on it. 

 
OP
B

BassDrop69

CarAudio.com Newbie
May 4, 2019
18
0
@DRBOOM thanks man, very informational. Now the way my box is designed is kinda similar to the underseat boxes, as it's not very deep to fit behind my rear seats. Just wide to make up the interior airspace. 

I dont have exact measurements right off my head right now but exterior is about 52"ish width 20"ish height and about 11" deep on exterior.. back wall is doubled so mounting depth inside is about 9". When the subs sits the back wall is about 3/4" from the magnet. 

Will being this shallow of a box have an effect?  

I've attached a picture. Sorry it's hard to see but the rectanglar port is passenger side front. 

20190506_234454.jpg

 

MattinMO

Senior VIP Member
Dec 31, 2017
696
116
St.louis, MO
Wait where is the port relative to the woofers? That pic is too dark and tells us nothing they could be sitting on a black carpeted floor for all I know 

 
OP
B

BassDrop69

CarAudio.com Newbie
May 4, 2019
18
0
Wait where is the port relative to the woofers? That pic is too dark and tells us nothing they could be sitting on a black carpeted floor for all I know 
Sorry that is the only picture I had on my phone of mine personally. Here is a picture from netaudios site of one similar to mine to show where the port and subs location is. 

dodge_ram_mega_cab_sub_box_02.jpg

 

Jeffdachef

Gunz That Turn on Nunz
Feb 5, 2013
17,414
301
South Coast Metro, CA
@DRBOOM thanks man, very informational. Now the way my box is designed is kinda similar to the underseat boxes, as it's not very deep to fit behind my rear seats. Just wide to make up the interior airspace. 

I dont have exact measurements right off my head right now but exterior is about 52"ish width 20"ish height and about 11" deep on exterior.. back wall is doubled so mounting depth inside is about 9". When the subs sits the back wall is about 3/4" from the magnet. 

Will being this shallow of a box have an effect?  

I've attached a picture. Sorry it's hard to see but the rectanglar port is passenger side front. 
those measurements are no where near 5.25 cubic feet.  its 5.14 before port and sub displacements and it sounds like there's extra thickness to the box as well. I'm pretty sure you are well below 4 cubic feet.  more like 3.5 to 3.75 cubic feet net airspace after all displacement.

image.png

 
OP
B

BassDrop69

CarAudio.com Newbie
May 4, 2019
18
0
those measurements are no where near 5.25 cubic feet.  its 5.14 before port and sub displacements and it sounds like there's extra thickness to the box as well. I'm pretty sure you are well below 4 cubic feet.  more like 3.5 to 3.75 cubic feet net airspace after all displacement.

View attachment 5549
Well now I feel stupid. I never double checked I just believed what net audio told me which was 5.25cft. Thanks. I just took actual measurements and its 60" width by 10" up top and 60" by 11" bottom. 18" height.

 
OP
B

BassDrop69

CarAudio.com Newbie
May 4, 2019
18
0
Sorry for the dp lol. 

I just read up some on the smaller/shallower boxes not letting the subs get the low bass extension. Like @DRBOOM said above. Sounds like my problem. I guess I had it backwards thinking it was 5.25cft and too big lol.

 

DRBOOM

CarAudio.com Well Known
Nov 21, 2018
249
51
With a box that big, it would be like infinite baffle system, like using your whole trunk area for the subwoofers.!

20150207_112508.jpg

 

DRBOOM

CarAudio.com Well Known
Nov 21, 2018
249
51
That's ok mate, they must have quoted you the exterior size, not the internal volume.  Since its tuned low, the internal volume has to be increased in size to accommodate for the tuning frequency.

All good mate!

20150228_215631.jpg

 
  • Like
Reactions: WJE
OP
B

BassDrop69

CarAudio.com Newbie
May 4, 2019
18
0
Figured it out. Found out my back and front walls were flexing so braced with some all thread rod. It made a world of difference. Excuse the sawdust I hadn't cleaned up yet when I took the pic lol. Thank for all the input guys

15621.jpeg

 
Last edited by a moderator:

Create an account or login to comment

You must be a member in order to leave a comment

Create account

Create an account on our community. It's easy!

Log in

Already have an account? Log in here.


Users Who Are Viewing This Thread (Users: 0, Guests: 1)



Trending topics

Latest classifieds