One should set the xo point one octave above the netural rolling off of the speaker,this would make the speakers,accoustic roll off "slope" quiet irrelevant IMO.
By the way, this only accounts for the high-pass side of the xover.
>What are you doing about the low-pass side?
>How are you calculating the low-pass value?
>How are you going to match the low-pass value with mains, center and surrounds that each have different low frequency rolloff characteristics?
What makes a zero degree phase offset, -24dB Linkwitz-Riley symmetrical xover so desirable, is it's ability to smoothly make the xover transition at lot's of different xover frequencies (read many different types of speakers) without causing big mismatches in the frequency response or peaks at the xover frequency.
[This message has been edited by bstan (edited November 04, 2002).]