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Discussion Starter · #1 · (Edited)
I have a 4 IB manifold. 2 IB's are facing in the manifold, and 2 I have facing out 'room constrictions'

What would be the correct way to wire these so they stay in series and all work in the same direction?

All IB's are 4 ohms, I want to finish with a 4 ohm load.


Would I be right in thinking:

Amp + to IB facing in +, - to IB facing out +, - to facing out +, - to the other IB facing in +, - to Amp -?

thanks.

Will
 

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Your picture doesn't clearly show all connections, just make sure you follow Mikes' diagram & you'll be fine.
 

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Don't they nee to be wired out of phase if they are pointing in opposite directions from the manifold?
 

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I've seen them wired both ways, out of phase is supposed to cancel box ressonance.
Actually I think it's the other way around - wired in-phase (so both drivers are either moving out together or in together) to cancel out box ressonance (if set up as dual-opposing drivers in the same box).

My subs are built this way from NHT (the W1's). They have two 12" opposing drivers. There is absolutely no resonance - even when cranked up, the box feels totally dead.
 

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^^^ I stand corrected, thanks for pointing it out. I looked at mine and yes -push/pull setup.
 

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Discussion Starter · #11 ·
I think you are correct, the 4 subs need to all push out from the manifold at the same time.
So with that in mind is your wiring diagram wrong Mike?

My home Internet is down so I can't up load my rectified drawing.

All I know is I've got mine pushing and pulling together, and my meter is reading 4 ohms so I think I'm Golden.
 

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Ok, now I'm confused. I just watched my subs playing some bass material. They do push out and in at the same time (they are set up so the backs are basically touching each other - dual-opposing). This makes sense in creating an anti-resonant speaker.

But I an see them being wired out of phase to work together - but that would seem to 'rock' the cabinet if done this way as they would be working together adding more force in the same direction.
 

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He does not have a cabinet, it is IB.

Mike's diagram is correct for drivers facing the listening space. For this case where two are reversed, the phase needs to be reversed on the ones facing the infinite space. i.e. Each pair needs to have + to + on the drivers and the - on each needs to connect to the amp + & -. Or vice versa.
 

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Discussion Starter · #14 ·
I was once told mounting one pair magnets in, and the other pair magnets out will cancel even order harmonics.

However the drivers must be wired so all the cones need to move in and out at the same time.
 

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Discussion Starter · #15 ·
He does not have a cabinet, it is IB.

Mike's diagram is correct for drivers facing the listening space. For this case where two are reversed, the phase needs to be reversed on the ones facing the infinite space. i.e. Each pair needs to have + to + on the drivers and the - on each needs to connect to the amp + & -. Or vice versa.
Cheers for clearing this up Icaillo, This sounds like how mine is wired presently.
 

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Not sure about this (I did one way back when but my memory is shaky on the IB). Usually IBs are done with a speaker pair, the space between being "isobaric", and only one speaker working into the listening area (the other into your box or infinite space). With a single manifold and 4 speakers as shown, you need to work each of the two speaker pairs (top/left & bottom/right) out of phase pressure-wise to get an IB with no pressure change in the manifold (which is what I assume you're shooting for), but that also produces little acoustic pressure into the listening area unless two of the speakers work into another manifold (which would be a sealed or ported box, or an infinite space). This circuit diagram (note speaker orientation) will achieve an IB in the manifold and produce 4 Ohms, but two opposing speakers need to be loaded into a box cavity (as shown in red). Both red areas can be the same space (or not). All of the speaker directions can be reversed (to have the top and bottom driver cones facing the listening area) but the electrical polarities will stay the same.

It's not the manifold whose resonances you're trying to cancel, but the non-linearities of the drivers which is achieved by working two of them (acoustically in series with each other) in opposite mechanical phase but identical acoustic phase.
 

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