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Discussion Starter #1
If you set a crossover does the drop off start at the frequency you chose or the next octave? For example you set a lpf with a 12db slope at 80 hz for your sub will it be minus 12 db at 81 hz? Or will it start dropping off at the next octave which is 160 hz?
 

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LPF: Low pass filter. Passes the low frequency's below its frequency. 160 would be -12 and 120 would be -6.
 

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At the frequency you choose for the crossover, assuming we're discussing active crossovers, the level is attenuated 0 dB. One octave higher the level is attenuated the amount of the slope. In your example the output is 12 dB lower at 160 Hz. This is why 12 dB slopes are not desirable for subwoofers, because it will be playing audibly well into the midbass region.
 

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A crossover frequency is the point at which the signal is down by 3db's.
So if you set it at 120hz than it is 3db lower at that freq then it will be down 12db at 60hz.If it is 12db/oct slope.
 

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A crossover frequency is the point at which the signal is down by 3db's.
Thanks. My bad for assuming incorrectly. Time to do some reading.
 

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Discussion Starter #6
I thought a crossover can be any slope? Well I guess what Im trying to ask is when does the crossover start cutting your speakers output? Is it the next octave or does it start right at the crossover point?
 

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Next octave like we have bin saying :D
 
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