Setting up LR4 active

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i have question about tuning LR4 crossover.

I have done linear phase and harsch crossover usually, seems that harsch does not work this application, it´s a car audio.

Want to understand more LR4, it just sounds better this application but theres that phase wrap.

okay that picture i posted has harsch and wrapping LR4.

So LR4 is tuned right when phase wraps on crossover point?

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so i tried to tune home audio funktion ones with factory presets and i got this, no wrap.

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they do polarity swap on LR4 between mid and high, i dont get it.

should it be wrapping or "straight" phase?
 
odd

no one reply.

so no one knows what lr4 system phase should look like?

with lr4 on i feel there is something difference going on, might be that lower xo point wrap.

my delays seems correct so i cant be any cycles of?
 
That looks like minimum phase curve to me. Check program settings!
In REW phase looks different with different IR gating, when more reflections get mixed to measurement, but in a good semi-nearfield measurement there shoud be 360¤ wrap at xo points. I have some LR2 and LR4 versions of same speaker, and phase graphs basically follow the rule.
 
I'm a bit out of my depth here with LR4 active filtering, but for sure, to achieve phase wrap, you actually seek an acoustic LR4 slope.

It is then positive polarity when time aligned.

You might actually want near BW2 electrical slopes with say, a 8" woofer and a 1" dome tweeter to get near LR4 acoustically. Because both of them have some mechanical rolloff. Life would be easier with dead flat drivers.

BW4 electrical and BW2 mechanical might add up to LR6. Deep stuff, eh? Now I'M confused! 🙂

Wait a minute. Two cascaded BW2 filters makes LR4 which is positive polarity. Two cascaded BW3 makes LR6 which is negative polarity. That's it! LOL
 
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i know those acoustic slopes.

its not issue with these.

my 10" goes easily straight to 1000hz, crossing 379hz
3,5" does well 200hz-10k crossing 379-4021hz
1" goes straight 2k-20k crossing 4021hz

didn´t need nearfield eq, just room eq