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Discussion Starter #1
Hi Guy's, I have just fitted a pair of RE XXX midbasses to both front doors.
The problem is, if I wire the up all in phase I get major bass cancellation! So I wired up 1 (in each door) out of phase. The midbass is back but don't sound good IMO well, at least as good as they should.

The drivers are mounted to an MDF baffle, oval shaped, next to each other. Each pair are run off a T600.2 (not 1 amp per side) 63Hz 24db/oct - 3.2Khz 12db/oct

Is there something I need to be looking at?
I have tried to EQ this problem out, but am still not 100% happy. I was thinking of possibly adding a third pair of these drivers at a later stage so running one pair out of phase is far from ideal anyway...
 

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these guys are power houses, your drop in bass could be from sucking up that much more power. i mean just 1 side with these and a ttweeter is gonna want like 200 watts RMS. so you should have 350-400 watts going to each side or could at least, i wuodln't run less than 300 per side for 2 sets though.
 

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did you try listening to one side at a time before you put one out of phase? having one out of phase on the same side will cause major cancellation.that's like having a sub backwards when you have two subs.
 

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Discussion Starter #4
Oops, I should of mentioned, I'm running them active. Each woofer gets 300+ wrms.

I did check each side individually. I'm stumped on this, I thought maybe having the drivers side by side in the same baffle might of had something to do with it.

That said, I have some midbass towers at home and they are wired in phase with no problems.
 

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my mids are about like yours cept i have no cancellation. i'm guessing you have it wired to a 2 ohm load per door? while keeping the mids in each door in phase with each other wire the left side outa phase from the right and see what happens.
 

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Do you really need 2 midbass per door? Have you tried 1 per door?
 

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i like my dual mids gives me more umph
 

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So there's no isolation at all? Don't dual woofers typically fare better when each has its own airspace?

I would think the air push/pull would be making them work against each other.
 

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So there's no isolation at all? Don't dual woofers typically fare better when each has its own airspace?

I would think the air push/pull would be making them work against each other.
thats why you have to run them in phase. then there is no cancellation. you can common chamber subs too, done many times.
 

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Try the pair nearest to you from 63Hz to 250Hz and let the other one whack from 63Hz to 3.2kHz... Then go back to playing with the polarity of the 63Hz to 250Hz pair...

It doesn't sound good coz you have 2 drivers playing midrange freqs... With 300rms per, you only need 1 pair to play midrange freqs IMO

Kelvin
 

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Verify if the cancellation is in the xover range or the drivers, I mean play only those drivers and see what you get that would be a wiring issue...or I would think it very uncommon for an amp to do that but anything is possible.
 

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Try the pair nearest to you from 63Hz to 250Hz and let the other one whack from 63Hz to 3.2kHz... Then go back to playing with the polarity of the 63Hz to 250Hz pair...

It doesn't sound good coz you have 2 drivers playing midrange freqs... With 300rms per, you only need 1 pair to play midrange freqs IMO

Kelvin
I don't see how running them into midrange territory is a bad thing, unless of course the drivers aren't designed to play that high.
 

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I don't see how running them into midrange territory is a bad thing, unless of course the drivers aren't designed to play that high.
I dont think he is saying it is bad thing, just that having two of them may be giving you ALOT more midrange than you need. maybe this is drowning out the midbass that you are striving to get. padding down the midrange will effectly raise midbass.
 

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Oh maybe too much midrange, I assumed the OP said 'midbass' and was playing a bass sweep or similar and also level matching to the existing subs. Anyone know what kind of IB response those drivers have?
 

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I don't see how running them into midrange territory is a bad thing, unless of course the drivers aren't designed to play that high.
Having 2 pairs of drivers playing midrange frequencies without any form of T/A is asking for trouble IMO. It's just gonna bring all kind of phase problems to the table...
Best thing to do right now is to get his system sounding "right" first. Therefore, he needs to focus on the pair (away from him) that will play higher mid freqs first. When he's satisfied, add the pair (closest to him) that plays midbass freqs and play with polarity. Then when it sounds "right" he can effectively raise his LP on the closest pair in order to get some volume that he's been wanting and stop raising when it messes with the midrange too much.

Kelvin
 

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I dont think he is saying it is bad thing, just that having two of them may be giving you ALOT more midrange than you need. maybe this is drowning out the midbass that you are striving to get. padding down the midrange will effectly raise midbass.
That is also a good reason. Thanks

Kelvin
 
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