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Discussion Starter #1
So focal utopia 4 way active, no. 7 + 21wx sub off a pioneer p99rs. All set up, been going for a few months, my install has the mid and tweet above dash near A pillars, and mid/bass in bottom of doors with sub in boot. It all sounds great, got it TA'd pretty much right in front of my face, however, when I reverse phase the tweet and mid above dash, everything becomes very, very centred, to the point where i feel like i can reach out and touch the band. Buuut, i feel like it looses all transition between the door speakers, is this purely because it makes the above dash speakers respond first, then the doors are a sort of mild echo a split second later? so in return im kind of cancelling out the natural transition between the speakers? I feel I loose the nice wide stereo image and blend but gain crazy pinpoint accuracy, also mid and tweet sound harsher when reversed, not as warm, much sharper (not really in a good way) Which is best do you think? The pinpoint accuracy is fantastic, there are no floating frequencies, but the field feels very narrow and a bit harsh. And why is this effect happening? FYI everything is crossed with a 36db slope with no gap between crossover points as I want NO overlap in sound between speakers for absolute detail and direction control.
 

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focal utopia 4 way active, no. 7 + 21wx sub off a pioneer p99rs.
reverse the phase on the 6.5" mid woofer instead and tune from there, the Focal No.7 Crossblock has the mid woofer in reverse phase by default for a reason.

You may be interested to know that ALL Focal Utopia Be 3 Way Floorstander for Home has the woofer in reverse phase.
 

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Reversing polarity will not change the arrival time of the sound only the relative phase. What is happening is a frequency response problem. Reverse both sides mid bass drivers and it should improve it.

I strongly suggest setting phase/polarity with your processing turned offf with the exception of crossovers. Get everything working and sound best without any processing then turn on the signal delays and equalization functions and the results will be much improved.

Eric
 

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Discussion Starter #4
leave the mid and tweet in normal phase then? Just reverse the mid/bass? and sub? Sub always goes reverse when I TA
 

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leave the mid and tweet in normal phase then? Just reverse the mid/bass? and sub? Sub always goes reverse when I TA
I would proceed as follows:

Turn all processing off EQ delays and leave high pass crossover on to components.

With midbass disconnected listen to spoken voice with mids and tweeters only and use the in phase / out of phase track from a test CD. Test reversing polarity of input to one crossover only. You are trying to get the most coherent focused center image.

Once you get the mid and tweeter relative polarity/ phase where it is best bring the midbass back in to it and leave the subs off. Listen at this point to height of stage and focus and placement of images. If its low reverse polarity on both mids to raise it up.

Add the subwoofers back in and set polarity/phase to get the best integration with midbass and anchor the sub up front.

If the midbass pulled the center to the side or killed the focus and EQ doenst cure that you can try reversing polarity of far side midbass from your listening position, in some instances it will kill all midbass attack in other it will improve it but in all it will require a sub to midbass crossover slope no lower than 70 hz typically.

Hope this helps

Eric
 
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