Help. Question about air-space, enclosure placement and potential.

[Jaguar 10+ year member]

I have a question about acoustical advantage of free air-space relative to subwoofer enclosure placement and potential. I ride with my seats down due to the tendency for the bass resonating from the subwoofers to get louder/deeper/cleaner. Seat to trunk is not sealed, the height of the enclosure I currently use allows the additional dimension of of a 4" height x 36" gap of unblocked/free air space for the bass to travel within the chamber of the vehicle itself, which, I believe lends an additional acoustic element to the set-up. Everythings fine why touch it right, the problem is im getting a new custom ported enclosure made which will house two sundown sa-12's, the dimensions of the box im told will have to be a taller, deeper etc to maximize the potential of said woofers. The problem is the dimensions of the new box would be around 18" in a 20" maximum height trunk which would cover the 4" height x 36 width gap, my current enclosure allows. I'm thinking of going a few inches deeper so I can keep some that free air-space, but not really sure it would matter as long as the seats are down. What would you do(?).

I'm told cubit's are cubits, so I suppose it would not hurt to go deeper if I wanted to keep that space, my trunk is around 32-33 inches deep, the depth of the new box in theory would be 23" deep. Here are a look at a few specs. The current measurements of my enclosure, 36"w x 16"d x 13"h. The measurements suggested for the Sa-12''s, 38"w x 18"d x 18"h. The measurements that would allow me to keep the air-space by making the box deeper, 38"w x 23"d x 13"h I'm spending good money to have the box made, just rather have it compliment the automobile I have, a 1999 Jetta. Anyhow, I'd also like to ask for anyone that's willing to help, are there any suggestions as to how the port and subwoofers should be aimed, whether port back, woofers up etc. Thanks.

Click to read more...

 

[BAPEKC 10+ year member]

I myself have the same car. I'm trying to do 2() 15's in a ported box through the cabin. Still wondering if I got over my head on this lol. I will keep eyes on this thread however because im almost in the same situation.

 

[Jaguar 10+ year member]

Can I get some help/advice from the senior/advanced members here. Any help is really appreciated. Thank you.

 

[T3mpest 10+ year member]

Best bet here is if your going to be blocking most of the space for the wave to go into the cabin then you need to block ALL of it and turn the box around.. Instead of using a smaller box and firing it rearwards to allow the backwave to enter the cabin, turn the box forwards and seal it off from the cabin.

 

[Jaguar 10+ year member]

Best bet here is if your going to be blocking most of the space for the wave to go into the cabin then you need to block ALL of it and turn the box around.. Instead of using a smaller box and firing it rearwards to allow the backwave to enter the cabin, turn the box forwards and seal it off from the cabin.

I've tried turning the box around facing the inside chamber of the vehicle with the seats down before, sounded really bad.

Any other advice on this, really need it.

 

[Jaguar 10+ year member]

Have to admit, I'm surprised at how limited the response has been to this, there must be someone out there who can offer some advice!

 

[T3mpest 10+ year member]

Well if you don't want to do that then make make the box a bit deeper and less tall.. you dont have to do 18 tall as long as you have be correct airspace still.. usually if your going to face the trunk kid the shorter the box the better. If your box gets very big a side firing port can help too but in your case is fire it all back at the trunk

 

[Jerhemy 10+ year member]

I've tried turning the box around facing the inside chamber of the vehicle with the seats down before, sounded really bad.
Any other advice on this, really need it.

When you face a box forward in your trunk like this, you have to seal it completely from the truck to the cabin, or else yes, it will sound like shit.

What are you going to be running the sa 12's with?

 

[Jaguar 10+ year member]

Well if you don't want to do that then make make the box a bit deeper and less tall.. you dont have to do 18 tall as long as you have be correct airspace still.. usually if your going to face the trunk lid the shorter the box the better. If your box gets very big a side firing port can help too but in your case is fire it all back at the trunk

Thanks for the advice.

I'm likely to go with a deeper box. 13" height is really quite minimal for two Sundown SA-12's, but then the depth would be in the 23"-24" area with a width of 38".

That would allow me to keep that open gap of air. I think I'm making the right choice, but if not I hope someone will let me know. Also having the box at 13" actually

allows me to pull the enclosure through 2"-3"s through that covey, with a taller box around 18", that 4" x 36" gap would not necessarily be completely sealed, but, I

feel keeping that gap of unblocked air-space allows the bass waves to have more free access to the chamber of the vehicle which creates an additional acoustical advantage.

When you face a box forward in your trunk like this, you have to seal it completely from the truck to the cabin, or else yes, it will sound like shit. What are you going to be running the sa 12's with?

Thanks for the advice.

I have a few amps on my shopping list, likely to be powering those with an MB Quart, but that's not final. The X1200M - Kenwood Excelon looks good.

I myself have the same car. I'm trying to do 2() 15's in a ported box through the cabin. Still wondering if I got over my head on this lol. I will keep eyes on this thread however because im almost in the same situation.

Well if you have a car like mine you know the trunk-space is not really that spacious, it's just enough to get away with murder and have some room left over

for things trunks are made for. My advice is to go with 2 higher end model 12"s, as opposed to going with two 15''s of a lesser caliber because the trunk space

on that vehicle might limit the full potential of 2 15"s, that is unless your willing to sacrifice more trunk space.

 

[BAPEKC 10+ year member]

Im at the point where i don't need to utilize the trunk at all. So using the full trunk i may be able to make the 2 15's happen. Feasible!?

 

[Jaguar 10+ year member]

Im at the point where i don't need to utilize the trunk at all. So using the full trunk i may be able to make the 2 15's happen. Feasible!?

Some of the more advanced members would be able to help you better, but it's certainly doable. It just depends on how loud you want to get (or feel you

need to get), you could make two 12"s sounds just as nice a two 15" it's all about setup, subwoofer choice, amplifier selection, placement, dimensions etc.

What 15"s did you have in mind. You said you wanted two.

 

[AnthonyO 10+ year member]

Another option would be to utilize the spare tire area for airspace in order to keep the dimensions down. But thats gonna require some fiberglass work.

 

[canaliJohn]

My sincere consent to you that you better go any local mechanic he will definitely help you out..

 

[Jaguar 10+ year member]

Thanks for the advice everyone, I'll probably go with a deeper box. Any other suggestions are welcome.

 

[Flex68 10+ year member]

"I'm told cubit's are cubits"

Putz is building a fukkin ark....