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Discussion Starter · #1 ·
Hey all,

I just finished the hard work on a full false floor and sub install, and I'll make sure to post my pics and all that later on. For now, I need to solve the subwoofer issue I ran into just now:

First, what's running is a 3Sixty.2 v2 on the factory HU, with only the front 2 channels pouring their output into the input of the processor. Then, the processor is sending 4 channels to my main amp (fronts are tweeters, rears are mids in an active configuration), and an additional mono signal to my sub amp via one RCA. Now, for the sub I run a splitter to the sub amp. This splitter is the solid block ones made by Monster Cable that are used in home theater applications.

The event that is happening is the sub is extremely weak when the balance is centered, but it gets incredibly powerful when the balance is brought left or right. In fact, when centered it sounds as if the sub is only playing the difference in bass between the left and right channels. Right away I'm thinking the sub is getting phase cancellation in the output of the 3sixty.2, but that's weird because the output is mono from the processor. Shouldn't it be summing this automatically??

Weird, huh? Help if you have any ideas. My first idea when I get home is to swap the polarity of the input to either the left or the right speaker-level inputs to the processor coming from the head unit.
 

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Discussion Starter · #2 ·
During lunch I went out at work and flip-flopped the polarity for the speaker level input on the processor from the head unit.

The bass now is strongest when played in the center as opposed to left and right extremes of balance. So, my theory was right regarding cancellation due to polarity, I think. At some point from the head unit to the processor I have made a miscalculation and must have wired one of them backwards. Which one? I have no clue since the deck wiring was done about a year ago and I don't want to pull it all apart again. What is very interesting here is that my older RF3sixty.2 v1 processor didn't have the same cancellation problem, and I think I know why. The V1 only pulls the bass signal from one channel. I can't remember if it is the left or the right, but I know that it does just this.

Now, to figure out phase on ALL the speakers to make sure I'm not leaving something on the table.,..
 

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Discussion Starter · #5 ·
Brilliant! I can do that, I have an aux input available on the 3sixty.2, and one on the stock head unit as well. I can compare-contrast between the two and get the right response.

I don't have a phase tester other than a good 'ol AA battery against the terminals. I don't like doing that since tweeters are involved, however.
 
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