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Rockford Fosgate Power 650 & Power 300

Have a question maybe someone can answer. On the old school Power 300s and Power 650s, when running high channel crossovers in "flat" position (dual stereo), it says to reverse low channel speaker outputs + and - color codes (reverse polarity if not using the internal crossover). I have attached a photo of the owner's manual showing (dual stereo) and a photo of the back of the Power 300 showing what I believe is (biamplified stereo). Why do you have to switch polarity?
 

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Wave Shepherd
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Re: Rockford Fosgate Power 650 & Power 300 - reverse polarity on low speaker outputs

Usually on a 2nd-order crossover (12dB/octave) one of the speakers will be wired with reverse polarity (either tweeter or the woofer, but not both).

Maybe this documentation is a hint about when you use (or do not use) the crossover on the amplifier, you should not (or should) wire one speaker in reverse polarity?

I wonder if the crossover on some modern amplifiers, when switched to "on" with a slider or switch on the amplifier, will also reverse the polarity of one of the channels for you? Seems like an interesting idea. I wonder if it would add more confusion or less.

-JZ
 

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Re: Rockford Fosgate Power 650 & Power 300 - reverse polarity on low speaker outputs

Have researched it but still have not been able to find a definitive answer.
 

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Re: Rockford Fosgate Power 650 & Power 300 - reverse polarity on low speaker outputs

I'm going to side with Justin Zazzy on this one. I'm certain it has to do with the 180-degree phase shift that occurs with 12 db/oct crossover slopes.
 

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Re: Rockford Fosgate Power 650 & Power 300 - reverse polarity on low speaker outputs

So when engaging the crossover to run bi amped stereo, it flips the polarity of the rear (low channels as it says on back of amps) outputs from what it would normally be to run dual stereo? On my Rockford Power Transana amps, I have always ran a Kicker KX3 external crossover, so I always wired + and - like normal. Never had to worry about it.

I am running a Power 1000 bridged on subs. Simple wiring. No problem. Running Power 300 and 650 on mids and highs. The front channels on both stay same + and - regardless of using internal crossover. On rear (or low channels as it says on back of amps), have to flip polarity. It is a little bit above my understanding of what it is doing and why. Why would usage of an internal crossover determine polarity when an external one wouldn't?
 
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