non-divided, shared chamber box question

[SHOKDU 10+ year member]

I've got two Alpine SWR-1023D's that are going into a shared chamber box. The box has adequate airspace, but my question lies in an old memory I have of shared chamber boxes. In the past I think I remember that when using two subs in a shared chamber box you have to wire the subs up in one particular way so that both subs are firing at the same time, etc. The diagrams I'm attaching are the two ways I can do the wiring in order to achive a final 2 ohm load. Is there a more "preffered" method?

I'd like to run the coils in series and the woofers in parallel, but just want to make sure that's acceptable for a shared chamber box.

Again, I appologize for the dumb question...it's been a long time since my last build and my memory is fuzzy.

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[marcotheclepto 10+ year member]

either one of those methods will work. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[SHOKDU 10+ year member]

Thank you for the reply. I think I figured out what I was remembering. When using a non-divided, shared space box you should run the subs in parallel or series to the same amp. Running two amps for the two subs is undesirable. Is that correct?

 

[daboyfrumdabx 10+ year member]

Thank you for the reply. I think I figured out what I was remembering. When using a non-divided, shared space box you should run the subs in parallel or series to the same amp. Running two amps for the two subs is undesirable. Is that correct?

Correct, two amps is undesirable unless they're strapped. It can be done, carefully, but never really recommended. The only time you really have to be worried when wiring for shared airspace is if you're inverting a sub. If you invert one of the two subs, you need to reverse polarity on one so they move opposite of each other. one cone moves in towards the motor while the other moves out and away from the motor, however both cones will be moving to and away from the box the same way. If that makes sense. More info than you needed but it'll be useful someday haha.

 

[schackel 10+ year member]

both

 

[SHOKDU 10+ year member]

Great, thanks guys!

 

[hoxie08 5,000+ posts]

Retroaudioinc is a scammer

 

[Buck 5,000+ posts]

If I read correctly you were under the assumption that subs had to be wired what is called in phase with each other only with a shared chamber enclosure. That is false. Not matter what the enclosure, the subs will need to be in phase- moving in the same direction.

 

[marcotheclepto 10+ year member]

If I read correctly you were under the assumption that subs had to be wired what is called in phase with each other only with a shared chamber enclosure. That is false. Not matter what the enclosure, the subs will need to be in phase- moving in the same direction.

yeah was gonna mention that. but was too lazy xD

 

[galacticmonkey 5,000+ posts]

Yeah, subs always need to be in phase. Even if you have one normal, and the other inverted, the inverted sub needs to be wired backwards to bring it back into phase with the other sub.

And to wire the subs, just go from a - on one side of each sub, to a + on the other side of each sub. That leaves you a open + on one sub, and a - on the other side on each sub. That brings each sub to 4ohm. Then just wire the + on each sub together and the - on each sub together. That brings it down to 2ohn. Then take the + and - from one sub and hook it to the amp. Thats a 2ohm final load. Its the way the bottom pic shows.

Just remember:

+ to + = Impedance goes down.

+ to - = Impedance goes up.