Sealed box for 4 12's

[Bostonjlguy 10+ year member]

I have a sealed box that was built for 2 12's. The box itself is about 26" wide 14 inches tall and 32 inches deep. The box has cut outs for 2 12's on the front. I planned to put the box in the trunk so those two subs would be rear firing. I would like to put two more 12's in the box; however, I cannot fit them on the same face of the box. I was thinking about putting them either on the sides of the box towards the back to keep the woofers as far apart as possible. I am curious if this will cause sound canceling due to being out of phase. The box is braced down the center currently making two separate chambers. I am wondering if it would be best to put two dividers to make it a four chamber box, or should I just build a box putting all subwoofers rear firing. I am putting these in a trunk so space is kind of an issue. I don't want to hear just go with a 15 or 2 12's. I have been doing car audio a long time and am looking to experiment and have a little fun. Suggestions please.

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[Ionakron 10+ year member]

lol. Experiment? mount the subs cone* to cone*. lol then you can fit them both on the same face!

edit-wire the subs on the outisde of the box out of phase.

 

[dirtyunclerandy 10+ year member]

could you do all four on the top of the box? I think that would be your best bet.

 

[Bostonjlguy 10+ year member]

Split into 4 chambers each compartment would be would be a over a square foot. Subs require a square foot. It is more an issue of sub placement and sound canceling.

 

---------- Post added at 11:49 PM ---------- Previous post was at 11:48 PM ----------

 

Can you do that with any sub? How does it sound?

 

---------- Post added at 11:50 PM ---------- Previous post was at 11:49 PM ----------

 

could you do all four on the top of the box? I think that would be your best bet.

I don't think they would all fit, and I would have to rip out the center brace

 

[Bostonjlguy 10+ year member]

lol. Experiment? mount the subs cone* to cone*. lol then you can fit them both on the same face!
edit-wire the subs on the outisde of the box out of phase.

So wire the subs isobaric and then wire the voice coils backward on the subs on the outside of the box?

 

[Ionakron 10+ year member]

yessirrr. Do it right and it'll be louddd.

 

[dirtyunclerandy 10+ year member]

you might need a new box. I don't think subs on the front and sides would sound very good. Sure someone with more knowledge will chime in.

 

[Bostonjlguy 10+ year member]

I think I will try that! For fun! I never thought of that. I have been doing car audio for a long time, but I posted this because of reasons like that. Sometimes its best to get ideas from other people.

 

[Ionakron 10+ year member]

I think I will try that! For fun! I never thought of that. I have been doing car audio for a long time, but I posted this because of reasons like that. Sometimes its best to get ideas from other people.

The whole push-pull(isobaric) idea likes smaller boxes tbh i believe but should still work to play around with. I'm not a car audio expert though. Someone feel free to chime in on this!

 

[Bostonjlguy 10+ year member]

yessirrr. Do it right and it'll be louddd.

How would you wire the dual voice coils. I was gonna wire them all together series parallel to get a 2 ohm load. My mono block does have 2 sets of terminals parallel to one another. So if I can at least wire two of them together to get a 4 ohm load, I can use the amp to get the final impedance to 2 ohms. What would that do to the polarity though. Would that mess with my amp having a positive and negative current?

 

[myjaja 10+ year member]

If you dont want to hear "keep the two 12's and put them in a good ported enclosure," then I say you can get a good idea from this guy.

 

[Ionakron 10+ year member]

How would you wire the dual voice coils. I was gonna wire them all together series parallel to get a 2 ohm load. My mono block does have 2 sets of terminals parallel to one another. So if I can at least wire two of them together to get a 4 ohm load, I can use the amp to get the final impedance to 2 ohms. What would that do to the polarity though. Would that mess with my amp having a positive and negative current?

Unfortunately i can't help you here. Unless you're amp has a Phase switch on it : p Somebody help this guy out! come on!

 

[Bostonjlguy 10+ year member]

Unfortunately i can't help you here. Unless you're amp has a Phase switch on it : p Somebody help this guy out! come on!

Being that I am an electronic technician, you would think I could answer this question for my self. I mostly deal with chip boards and chips.

 

[hispls 5,000+ posts]

If you're dead set on the idea, where you mount them in the box shouldn't make a lot of difference. For preference I'd do 2 firing back and 2 firing to either side, though up and back may do about the same.

 

[Bostonjlguy 10+ year member]

If you're dead set on the idea, where you mount them in the box shouldn't make a lot of difference. For preference I'd do 2 firing back and 2 firing to either side, though up and back may do about the same.

Yes, but you can actually have sound canceling which would make 4 subs pointless at that point it would be the same with 2