Crossover Slopes & dB down points

I'm kind of curious as to where the measurement for a crossover should be taken with the various types and slopes. I vaguely remember soundhound saying -3db for 12 db/octave slope and -6db for 24 db/octave slope. Is that right? And does the crossover type matter? I mean insofar as Linkwitz/Reiley vs Butterworth. And just for fun, what about an 18db and a 48 db slope? How about mixing and matching slopes. Like for the (seemingly) more common 12 and 24, if one was a 12 and the other a 24 would they both go from the same db down point or would each use their respective point I listed above?

Obviously it's where it sounds best, but in theory where should it be? To give a good starting point at least.

For Linkwitz/Riley 24dB per octave, it is -6dB. For 12 & 18 dB per octave Butterworth, it is -3dB. Mixing slopes will vary, depending on the slope. You must also take into account the cutoff slope of the speaker if it coincides near the crossover point.

Yes. I have a project I'll be working on (hopefully) where I'll really be stretching the limits before the natural cut-off slope comes into play. The -3dB points are fine, it's just getting them to blend together properly. If it works, this'll really rock.

Now, I've seen plenty of times where it's been said that it's very nice to have the crossover about 1 octave away from the -3dB point. Does that still hold for the 24 (or even 48) as it is much quieter at the octave away when compared to the 12 db/octave slope? Basically I'm wondering if I could get it at least 10db down (or more) before the natural cut-off slope begins to have an effect, if it would really make a much of a difference in the response. Like does the 24 dB/octave slope need to hit 24 dB down, or would 12dB down where the natural cut-off comes into play be enough as this is the drop-off is the same amount as with the 12 db/octave slope. It's just steeper. I'm asking because I think it's going to be close enough where that could make a difference.

Am I fussing too much over this? :p

At least the speakers I have seem to have generous over lab between mid-woofer and tweeter limits. I’ve tried different points of crossover but there wasn’t audible difference to me however, there was noticeable difference of sound characteristics when using different slopes such as L/R or Butterworth 24 and 12.

Just my 2 cents…