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Discussion Starter #1
I have 3 Boston G5 10s in a sealed box. Im using a HRU.2 amp.

This is how they are wired. The subs only have 1 terminal but they can be switched between 2 or 8 ohm.


The problem is the first sub moves a lot, the next one a little less and the last one barely moves. I noticed this same issue wiring subs this way a few years ago. The question is am I crazy? Or has anyone else noticed this? Im sort of screwed because I cant wire them any other way. The amp is only stable 4 ohms bridged.
 

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Discussion Starter #3
They should all move the same-double check your wiring-if any sub is wired to 8ohm rather than 2ohm it'll pull more juice and bump more.
Wiring is good, plus the fuses only go in one way to make it 2 or 8 ohms. Like I said, I noticed this issue with wiring like this a few years ago, it annoyed the crap out of me.
 

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if you are 100% sure that each sub is wired to 2ohms, then it is only the mechanical stiffness of each sub that is effecting it. give them some time to break in and see if that makes a difference.

are they all common chambered or do they have dividers?
 

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Discussion Starter #6
if you are 100% sure that each sub is wired to 2ohms, then it is only the mechanical stiffness of each sub that is effecting it. give them some time to break in and see if that makes a difference.

are they all common chambered or do they have dividers?
I went with a single chamber based on lessons learned from wiring up my last triple 10 box with 3 D4 subs, man that was a LOT of wire. This wiring job was very easy this time. Only 2 strands and a jumper between each.
 

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I went with a single chamber based on lessons learned from wiring up my last triple 10 box with 3 D4 subs, man that was a LOT of wire. This wiring job was very easy this time. Only 2 strands and a jumper between each.
ok, just checking. if they were divided, then that could explain it too. (different volumes of air, etc)
 

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Discussion Starter #8
Well, I guess I was wrong about the wiring causing the issue, I simply went and switched the middle sub with the left sub, and now the middle sub moves the most. This pretty much ruled out the wiring being the issue. I guess Ill just run it and be happy, because it does sound amazing!
 

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ahhh, sounds like a standing wave issue. they are converging in the middle and pushing ht center sub a little more.

if you really want to fix it. add some baffles inside the box to break up those waves.
 

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Discussion Starter #10
ahhh, sounds like a standing wave issue. they are converging in the middle and pushing ht center sub a little more.

if you really want to fix it. add some baffles inside the box to break up those waves.
Well, before I swapped subs the left one was moving the most, now its in the middle and still moving the most, so its either suspension or slight variation in impedance.

Ill cheggit out after a few weeks of break in, I got them on ebay and they were supposedly brand new, but they all have some marks on the mounting holes, so who knows how much each was really used.
 

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Shouldn't have any standing wave issues, 100Hz=3.447m wavelength, 60Hz=5.745m wavelength.

How compliant are the subs in relation to each other?

Edit: I'd guess they are 2nd hand and have each seen differing amounts of play.
 

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Is the one that moves the one with the marks on the mounting holes? If so you've got your answer.

Sounds like you bought two newish subs and a slightly new sub. Gotta love eBay.
 

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Discussion Starter #13
Is the one that moves the one with the marks on the mounting holes? If so you've got your answer.

Sounds like you bought two newish subs and a slightly new sub. Gotta love eBay.
They all have mounting hole marks:(
 

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Well, before I swapped subs the left one was moving the most, now its in the middle and still moving the most, so its either suspension or slight variation in impedance.

Ill cheggit out after a few weeks of break in, I got them on ebay and they were supposedly brand new, but they all have some marks on the mounting holes, so who knows how much each was really used.
nevermind then, I misread what you said. I thought you said the symptom followed the location.
 
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