help with my sa-10s

[blowthemup 21]

I have two sundown audio sa-10s that i'm not to happy with. They're not getting very loud at all off a saz2500d and i think my box is to blame. I designed and built the enclosure myself, its suppose to be 2.5cubes after displacements tuned to 32hz but not sure how well that worked out. Im at the point where i'm considering selling the 10's and upgrading to 12's or a single 15 cause i'm frustrated with how they sound. I can try a new box but would hate to put the time and money into it if thats not the problem. Current box dimensions are 30x20x14 exterior and the port is 3x12.5x31. I would greatly appreciate some help on my situation, thanks in advance. My old system was a 15" Fi SSD in 4 cubes @ 32hz off a memphis mc1000d and it was noticeably louder.

Edited December 30, 2013 by blowthemup

[altoncustomtech 773]

One thing that is contributing to the difference is that even two of those 10's doesn't equal the cone area of the 15" SSD.  Then consider that the xmax is nearly the same between the SA's and the SSD and the SSD could plain and simply move more air with each stroke than the 10's can.  Since it can move more air it's going to be louder in general.  

 

According to a few quick checks your box is pretty well spot on according to the dimensions you gave.  My question is whether or not it's a problem with HOW they sound or how LOUD they get because you go back and forth between those two words in your post.  

 

Are you certain you don't have any air leaks in the box?  Around the subs, all the seams, etc., if it's not pretty much a perfect seal it will affect the sound and output you're going to get from the subs.  I've asked this question a million times and the first thing people tell me is that they don't have any leaks.  You'd be surprised what and where leaks can happen, around mounting screws, under the rubber gasket on the sub, seams that looked perfect.  Are you able to move the box around?  See if maybe the placement is a problem.  If that's not the problem or a possibility then depending on your real issue with the sound or output kind of depends on the next steps to take.  

[altoncustomtech 773]

I looked at the numbers a little closer.  Assuming 3/4" construction and no bracing the internal volume is more like 2.75cu.ft. NET and the tuning is pretty much right at 32hz.  

 

If you want to know if the enclosure is causing a problem cut four pieces of 2x4 about 21" long, screw them together, wrap them with a little cloth so they don't make any noise from rattling inside the enclosure and place them inside somewhere out of the way of the port.  That will lower the internal volume down to 2.5cu.ft. NET and the tuning will only raise to about 34hz.  That will be a quick, cheap and easy way to see if the enclosure design itself is causing you an issue.  If it sounds more like what you're looking for then you can play around with more 2x4 or build another enclosure.  If it doesn't get you any closer to what you're looking for then you'll likely be needing to look into a pair of twelve's or going back to a 15 to get the output you're looking for, if the issue is indeed just the output.

[blowthemup 21]

First off thanks for the detailed response and I would like to clarify that they sound good just lack of output compared to my old 15" ssd. The box is double baffled so that would take up a little bit more room but not quite enough to bring it down to 2.5 cubes. How does lowering the enclosure volume affect output? I can't say for sure about the box being leaky. It is my first box that I built and my cuts weren't perfect but i used lots of caulk to make sure it was sealed but it could be leaking. It has good sound and I can't feel or hear any leaks coming from exterior of box so possible leaky port on inside but I want to doubt that. Back to air movement, air moves like mad crazy inside the port but not so much out of the port. Do I have enough port area? Makes sense that the 15 was louder because of more air movement from more cone area. Wish I knew that before getting the 10's, I foresee a 15 in the very near future for me.

[altoncustomtech 773]

Lowering the internal volume of the enclosure changes the alignment and therefore the response of the enclosure.  Coupled with slightly raising the tuning it could help bump up the response near tuning and help some with output.  Smaller enclosures tend to be peaky in response, which we don't necessarily want, but just a few tenths of a cu.ft. won't make that big of a difference and will show you with ease whether or not the enclosure alignment is at fault or if they're just not up to snuff.

 

 

Leaks can be a pain to find if you suspect having them.  If you sealed it up real good then I wouldn't worry quite so much about that particular issue yet.  The double baffle does make a difference, about .15cu.ft. actually so the NET volume is closer to 2.6cu.ft. but I would still try taking out a little box volume with the 2x4's and see where it gets you.  Again it's much cheaper and simpler than a new enclosure or sub(s).

 

If you're looking for more output than the 15" with about the same size enclosure you might look into a pair of 12's.  They'll have a bit more cone area than the single 15 and all things being equal have the potential to give just a tad more output.

[blowthemup 21]

Did I give them enough port area? Well all I can do at this point is play around with box position and like you said throw some 2x4's in there to lower the enclosure volume some. Doing this may help but I think i'm chasing my own tail here being what you said about cone area. After gaining a little knowledge i'm sure I want to go bigger subs. I like the simplicity of single 15"s so i'm leaning in that direction. I'm really thinking about a DC Audio XL 15", should be close to the same size box.