Question about calculating crossover slope

[quick01]

I’m running a RF T400-4 set to High Pass at 50 Hz for my 6.5's in the doors. The amp has a fixed crossover slope of 24db. What’s the actual low frequency cutoff? I'm guessing around 44Hz.

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[quick01]

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[Etac 10+ year member]

wat?

 

[n2audio 5,000+ posts]

he wants to know at what point the LF is actually removed from the signal reaching the speaker.

I'm doing it assuming crossovers roll off at a linear slope, which they don't, but I think it's a reasonable approximation. Someone who knows how to apply logs will have a more accurate calculation, but the way I figured it...

If you have a 24db/oct crossover set at an F3 of 50hz at a base power of (for simplicity) 100w

the speaker should see half the power at every 3-1/8hz.

The 0dB level would be 53.125, f3 or -3dB (50w) @ 50hz, f6 or -6dB (25w) @ 46.88, f9 (12.5w) @ 43.75hz, f12 (6.25w) @ 40.6 etc.

Hopefully that's in the ballpark. I think that's off by a step from my CS reply Quick.

 

[Etac 10+ year member]

i didnt check your math and im sure its fine, this is just to the op..

dont forget where the crossover point is.. its -3db's

 

[quick01]

he wants to know at what point the LF is actually removed from the signal reaching the speaker.
I'm doing it assuming crossovers roll off at a linear slope, which they don't, but I think it's a reasonable approximation. Someone who knows how to apply logs will have a more accurate calculation, but the way I figured it...

If you have a 24db/oct crossover set at an F3 of 50hz at a base power of (for simplicity) 100w

the speaker should see half the power at every 3-1/8hz.

The 0dB level would be 53.125, f3 or -3dB (50w) @ 50hz, f6 or -6dB (25w) @ 46.88, f9 (12.5w) @ 43.75hz, f12 (6.25w) @ 40.6 etc.

Hopefully that's in the ballpark. I think that's off by a step from my CS reply Quick.

n2audio: Good info Thx!

 

So...can I just double those figures if my amp does 200W per channel?

 

[n2audio 5,000+ posts]

yeah, every power level would be double.