Hey guys I'm thinking about buying a 2001 F-150 ext. cab this week and I was wondering which option would be better for putting my 2 12's in it...

1) Build two separate boxes
2) Build one box to fit box twelves..

Only answers from people who know what they're talkin about because I wanna know which option will be louder, hit harder, etc...

 

Multiple subs typically share a common box. I did some experimenting with this a few years ago when building sub boxes. I did single boxes, one box with separate/sealed chambers, single box with single chamber....

The SPL level was determined by the number of drivers, power to the drivers, and box design in terms of ported vs. sealed vs. nth order bandpass boxes, etc.

There has been some theory about the loading affect that one driver has on another and the impact of mminor differences in the suspension of supossedly identical drivers, but this never adds up to anything.

Most people go with a single box just for the convenience and cost of not having to deal with multiple boxes that produce no added benefit.

 

Where are you expecting on putting these? There isnt alot of room in the back seat, so you might have to make 2 boxes so the subs dont take up the whole back seat. If you figure out a good place to put them share the wealth.

 

All subwoofers should have their own airspace regardless of whether they share the same box or not. If they share a box, then there should be a divider between the two. This will also act a brace for the whole enclosure. If a sub solely uses its own enclosure with proper airspace it will hit harder. If it shares airspace then the bass will be deeper but not as loud. Hope this was understandable.

 

Thats not true. Whether the sub has its own airchamber, or shares it, it doesnt matter given that the airspace shared between the 2 subs is the same that they would get in seperate chambers. The sound quality, SPL, etc will not be significantly affected by using one over the other. One box is easier and cheaper, so I suggest that if you can fit it.

 

I've seen this issue a few times. When dealing with a sealed box enclosure, multiple drivers, and one air chamber, the multiple drivers can have an affect on the overall loading (Q factor) presented to each driver. For this reason, many boxes that hold multiple subs (even non-sealed units) keep things simple by arranging for each sub to have its own air space. This is done even with one box by just inserting dividers as 302V8 suggested. Some boxes are specifically designed with two or more drivers sharing a common air space in a sealed environment, like the compound (push/pull) design where one driver is mounted in a standard fashion and the other is mounted backwards and also wired in reverse. The difference between the push/pull and the more standard approach of both drivers facing forward in the same enclosure is that the push/pull environment is supposed to cancel out harmonics, but experts can seem to agree on whether it is odd or even harmonics that are cancelled.

Many box builders will tell you though that using separate chambers or a common chamber makes no difference. Side-by-side listening seems to confirm this (at least ones that I've witnessed - but we weren't trying to be overly scientific about it either). Two subs sharing the same air chamber will require twice the size cabinet and offer an increased efficiency of 3dB (twice the volume of a single sub). Frequency response is the same for a single driver in an enclosure exactly half of the size.

 

Morcutt- I'm only 17 man, I don't understand half the stuff your sayin about audio.

So pretty much what your saying is that it is up to me..?

 

Wow - I was 17 once.... But then, that's another story altogether...

You hit the nail on the head - go with separate chambers or one chamber - won't make any difference for you. The other thing to consider is what kind of music that you listen to and how much space you got for your sub box. You referenced "louder, hit harder", so I'm guessing 'that ain't no Hank Williams (Sr.) song" you're listening to. I've assumed that you were looking at a sealed enclosure. I assumed this because they occupy less space and have a flatter, more predictable bass response than their ported counter-parts. However, there is no beating a ported box for bass impact. So, if your music demands it and you can afford the space (a ported box will be twice the size as the sealed box typically), nothing will hit harder than a ported box.

 

Morcutt you're gonna confuse this kid. What he's saying is whether you build two boxes or one, make sure they have seperate chambers. Well if you have two single boxes of course they're not going to share chambers lol. What you need to supply us with is what kind of music you're listening to, what you're running in there, what effect do you want? I just turned 18 about 2 months ago.. wow doesn't seem that long ago, so I might be able to translate lol.

 

Translation, Booming *** bass that makes screws come loose and metal bend

Oh yea good insurance to pay for all those years of it, For the Ear doctor.

 

Haha, I was sitting at a red light this morning and had my stereo on, and my friend was in the car next to me and he looked at me with a surprised look on his face. We got to school and didn't see eachother till lunch, and then he was like Jerome, dude.. my gas pedal was vibrating, so I asked him what he was talking about, then I remembered being at the red light next to him.

 

haha nice story.

Anyways, yea i want some "Booming *** bass that makes screws come loose and metal bend"

I listen to lil jon, 50 cent, lil scrappy, ludacris, all them guys that have extreme bass.
I really don't like lil jon and people like him because you can't understand half the **** they're sayin especially when you're a country white boy from Indiana. Anyways..Does that mean a ported box would take up the whole back seat of an ext. cab??

 

Alrighty for that you're probably going to want ported, as this will sound louder, and will give you more impact. I have sealed, but I listen to rock too, so I like a little more of the quality. But you're going to be listening to bump bump bimp bump bump type stuff. If you buy the extended cab, or if you did, are you planning on throwing people in the back, or do you want a sound system back there that looks cool? If you're going to throw people in the back, you're going to need a way to hide the subs, or something so people have a place to sit. You have to take this into consideration. But it looks like you're going to want a ported (vented) enclosure.

 

Yea, that is mainly what I'm lookin for is all bass. If I do get that ext. cab I will want to put people in the back, so I don't know for sure what I'm gonna do yet. I think I'm going to say screw subs when I get that ext. cab, if I do, because that is the main reason I'm getting it-so I can have more room. So I don't know, but I'll post and let you know what I do..