Linkwitz-Riley Crossover

[Gsal]

Hello. In an effort to educate myself I have recently read about the Winkwitz-Riley type crossover. It is said to offer correct phase and time coherence. I'd appreciate any comments RV (or others) might be able to offer regarding it vs the 1st order crossovers used in the Vandersteen designs. Thank you.

[Holmz]

LR2 needs the speaker q80 degrees out in phase in the XO band, so that speakers needs to be inverted to get the phase coherent in the XO section… and hence I think that the step response takes it in the shorts.

LR4 has more delay so it is a cycle delayed and the woofer needs to move forward, or DSP delay needs to be added.

All of them seem more like a DSP active XO, crossover schemes than a passive scheme. But I suppose a butter worth can be passive, so 2 or 4x of a butter worth can be done in hardware.

 

Then it also depends on how the speakers beam or their dispersion/radiation pattern.
It is usually smoother spatially to  have the speakers sharing the load and the radiation pattern doesn’t step as fiercely (or smaller derivative, with respect to frequency.

[Gsal]

16 minutes ago, Holmz said:

LR2 needs the speaker q80 degrees out in phase in the XO band, so that speakers needs to be inverted to get the phase coherent in the XO section… and hence I think that the step response takes it in the shorts.

LR4 has more delay so it is a cycle delayed and the woofer needs to move forward, or DSP delay needs to be added.

All of them seem more like a DSP active XO, crossover schemes than a passive scheme. But I suppose a butter worth can be passive, so 2 or 4x of a butter worth can be done in hardware.

 

Then it also depends on how the speakers beam or their dispersion/radiation pattern.
It is usually smoother spatially to  have the speakers sharing the load and the radiation pattern doesn’t step as fiercely (or smaller derivative, with respect to frequency.

Thank you for your input. Not a fan of DSP.

[Richard Vandersteen]

The only crossover (without DSP) that is "Time and Phase Correct" is first order!  There is some confusion (some deliberate) that if all of the drivers are wired in phase the speaker will be "Time and Phase Correct", this is not true.  If you go to the specification section of the TREO CT and above on this site, you will see what Time and Phase Correct speakers measure like.  I wish I had time to use this forum as a classroom on speaker design or write a "Cookbook" on time and phase correct speakers, but I don't have the time and this forum is not the place.  Guys, lets focus on how Vandersteen owners can optimize (not redesign) their speaker's placement, associated equipment, solutions, new or old music and experiences.  For most of the forum members this technical stuff is "Babble".  Technical questions about Vandersteen are what this forum is about in search of solutions.  Thank You.  RV