# Crossover freq overlap?

Discussion in 'Archived Threads 2001-2004' started by MikeHalder, Feb 1, 2002.

1. ### MikeHalder Stunt Coordinator

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Through base management on my STR-DA7777ES I have my KLF-30 mains and my KLF-10 surrounds set to small @50hz and my LFE also @50hz. My question is will this create a 'sonic gap' at 50hz for those speakers?I remmember reading that at the x-over point there is a 3 db drop. If there is a 3 db drop at both the high pass and low pass filter (50hz), will that translate into a dip in the freq response or will the sum of the two outputs compensate at the 50hz x-over point? I hope I made sense in formatting this question

TIA,
Mike

2. ### John Kotches Cinematographer

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In the curious thing that is dB arithmetic (also logarithmic arithmetic ), -3dB * 2 = X
For instance, if your target is 75dB, 72dB + 72dB = 75dB.
So the -3dB adds out to equal flat across the drivers.
Regards,

3. ### ling_w Second Unit

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Doesn't the THX specification for subwoofer low pass have to be a L-R 24dB/oct crossover? If it is, then the cutoff point would be -6dB. I know if you summed it with an L-R high pass, you would get a accoustically flat response. But how would the response be if one followed the THX specification and used a 2nd order high pass, whose cutoff point is -3dB?

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