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Related, but I have been wondering this as I explore fail safes in my system. Does have two filters like this create any phase issues?
As long as they're outside of the passband of the crossover: not really. Having cascaded filters as close to one another as OP does will change the acoustic slope of the crossover which will result in improper summing. You primary fail safe should be a capacitor higher than the resonant frequency of the tweeters. 1.5-2x will offer more protection in case you don't remember to turn an XO on. A cap will also protect against an amplifier fault which could send DC to a tweeter and kill it.
 

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As long as they're outside of the passband of the crossover: not really. Having cascaded filters as close to one another as OP does will change the acoustic slope of the crossover which will result in improper summing. You primary fail safe should be a capacitor higher than the resonant frequency of the tweeters. 1.5-2x will offer more protection in case you don't remember to turn an XO on. A cap will also protect against an amplifier fault which could send DC to a tweeter and kill it.
Got it, thanks. I just installed caps in my car after a losing a set of tweeters due to a failed DSP. Was wondering if that was my only means of protection.
 

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Got it, thanks. I just installed caps in my car after a losing a set of tweeters due to a failed DSP. Was wondering if that was my only means of protection.
It should be sufficient. If you want an additional fail safe set the XO on your amp close to where the caps are as well. As long as the rolloff for these is far away (close to an octave) from the actual crossover point it shouldn't have an audible effect.
 

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Discussion Starter · #48 ·
As long as they're outside of the passband of the crossover: not really. Having cascaded filters as close to one another as OP does will change the acoustic slope of the crossover which will result in improper summing. You primary fail safe should be a capacitor higher than the resonant frequency of the tweeters. 1.5-2x will offer more protection in case you don't remember to turn an XO on. A cap will also protect against an amplifier fault which could send DC to a tweeter and kill it.
So you’re saying that if the DSP hp is set at 3600, having the amp hp set as close as 500-750hz lower would change the slope in a negative way? But the 2.2khz caps I added would be fine being the fs of the tweeters is 900hz? So no amp crossover, turn it to full range?
 

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So you’re saying that if the DSP hp is set at 3600, having the amp hp set as close as 500-750hz lower would change the slope in a negative way? But the 2.2khz caps I added would be fine being the fs of the tweeters is 900hz? So no amp crossover, turn it to full range?
Why would you use the crossovers on an amp AND a DSP?
 
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Failsafe in case the DSP settings are lost or corrupted, or other DSP failure.

As someone who had this happen, and lost tweeters, I can see why you'd do it. I have caps on my tweeters now.
He said he also has caps on the tweeters. Using the amp XO along with a DSP just seems redundant and pointless.
 
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So you’re saying that if the DSP hp is set at 3600, having the amp hp set as close as 500-750hz lower would change the slope in a negative way? But the 2.2khz caps I added would be fine being the fs of the tweeters is 900hz? So no amp crossover, turn it to full range?
Yes. Absolutely. From a SQ perspective the easiest way get symmetric crossovers is to use LR24 on a dsp and then EQ down to target. The 6 db/octave cap at 2.2khz would have some effect on a crossover of 3600 but would be 100 percent workable contrary to what anyone tells you.

If you are running amp crossovers in this system as well as dsp crossovers AND caps i would eliminate the amp crossovers just to eliminate a variable that might be causing you to clip gains or some other type of shenanigans. Idk there's been a lot of helpful info posted here i imagine between all the feedback you could test and report back what was going on.
 

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Who knows what he has from said...
10db equals double the loud which equals 10 times the power, but wait there is a compression ratio. What Im saying is there is a point where you can add more gain but efect will be lesser due to compression factor eg. "Lossing output"...
Dsp and amplifier crossovers can stack; considering which slopes and types you stacked probably the result was something like cheb type crossover with high slope where big peak occured before roll off.
 

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Are you making eq boost adjustments on the tweeters? If you are, don't. Just make cuts to flatten the peaks. If you are and they are over 3db that's an issue.

I bet your friend is turning on loudness or some sound settings to get louder or he is turning up gains.
Without o-scope readings, eq adjustments, headunit settings, etc we're just guessing.
 
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