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Discussion Starter #1
Curious. If you have a dsp and coming out of the dsp is a two rcas, going into the sub amplifier. If each rca has a 24db slope and the signal is summed inside of most monoblocks. Would you end up with a 48db slope?

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I don't think so because when I sum the signal in the processor I get a notable increase in output.
 

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Discussion Starter #5
RCA's don't multiply the XO freq.
If u cascade two 12db slopes. You get 24. So why wouldn't two rcas with 24 db at 100hz slopes, summed in the monoblock. Come out as 48db at 100hz?

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If u cascade two 12db slopes. You get 24. So why wouldn't two rcas with 24 db at 100hz slopes, summed in the monoblock. Come out as 48db at 100hz?

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Why do you think that summing two RCA cables from the DSP would be cascading them?

I guess the better question is do you WANT a 48db XO or a 24db XO?
 

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Discussion Starter #7
Why do you think that summing two RCA cables from the DSP would be cascading them?



I guess the better question is do you WANT a 48db XO or a 24db XO?
Thats kinda what im asking. Was wondering if summing=cascading.

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Both rcas have the exact same signal. So everything is just increased.
This.

Cascading is one into another, then to the amp. What you are doing is just combining 2 identical signals.

When cascading, the first filter acts then it goes into the next filter and that filter does its thing multiplying the filters because it was used twice.

Combining 2 channels aide by aide just adds them together. Everything stays the same except output, which is increased.
 

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If you combined the two inputs prior to the DSP, input the signal into Channel X of the DSP. then routed the Channel X output into the input of Channel Y, and had the same 24 db/oct XO on Chanel Y, then the output of Channel Y XO would be 48 db/oct
 

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Think about what crossover slopes actually mean. So let's say your low-pass crossover point is 80Hz and your reference level is 100dB. If the slope is 24dB/octave, then the signal level will be (100-24 =) 76dB at the next octave point of 160Hz.

Combining 2 such signals will not cause the signal level to drop above the crossover point. In fact, it would increase the signal level by about 3dB at all freqs. So the signal would now be 103dB below 80Hz and 79dB at 160Hz.

Cascading, on the other hand, can produce the drop u describe. The 1st crossover knocks the signal down by 24dB, and the 2nd crossover drops it down by another 24dB. But when cascading, it's best if both crossovers have the same crossover point and slope. Otherwise, multiple phasing issues will result, making it more difficult to blend the affected speakers into the rest of the system.
 
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