[Wayne A. Pflughaupt]

JasonB wrote:

Wayne,

I hope this is a clearer explanation....

My issue is not with the slopes themselves, I believe those are correct. My issue is where the initial roll off starts. An 80 hz 12 db per octave low pass filter should start to roll off at lower frequency than an 80 hz 24 db per octave filter. The crossover slopes on the REW are the opposite, the 24 db per octave low pass filter starts rolling off at a lower frequency than the 12 db per octave filter.

Also, if the crossover slopes are based on 2nd and 4th order Linkwitz Riley topologies they should both be down 6 db at the crossover frequency and neither are in the REW.

Thanks Jason, that clears it up nicely. Phrased like that it appears you know a lot about crossovers – more than I do apparently (not a hard status to achieve, I assure you, as you probably noticed from my misstatements in my previous post). I had to go searching for confirmation of your assertion about the 12 dB filter starting at a lower frequency than the 24. I came up with this:

Linkwitz-Riley alignments.svg[1] a.jpg

I think brucek has already ably answered your question; I dont think REW claims to be showing Linkwitz-Riley alignments.

Regards,
Wayne