[ekovalsky]

I decided to experiment with LeCleac'h crossovers, replacing my LR4 with them.  Results are very encouraging and I was wondering if any others have tried them.

Basically the LeCleac'h crossovers are 3rd order Butterworth using distracted shoulder points, polarity inversion of the midrange (in a three way system), and delay manipulation to create a minimum group delay condition across the audio band.  The goal is to have frequency response sum to within +/- 1dB all while minimizing phase distortion of fundamental from harmonic frequencies.

There is still some tweaking to do, but what I hear is very impressive.  Soundstaging is incredible.

If anyone is interested in reading about them, more information can be downloaded at these links:

http://freerider.dyndns.org/anlage/LeCleach1.zip
http://freerider.dyndns.org/anlage/LeCleach2.zip

[Jon L]

That's interesting.  Once you get into digital crossovers, the possibilities are endless.  I've been having good luck with Chebychev crossovers over Bessel and Butterworth, and I have to feel sorry for those poor speaker designers who have to forever tinker with passive crossovers
 
http://www.audioholics.com/techtips/audioprinciples/loudspeakers/speakerfilterscrossovers.php

[JoshK]

This is also why many designers are moving to a DEQX or equivalent (SoundEasy will do it too via computer) to experiment with xo topology and then committing to passive. This is the first I have heard of LeCleac'h, will have to read up further.

Another one to read up on is Jon Marsh's Cauer-Elliptic style LR8.  Its LR4 like in its phase & group delay while obtaining a LR8 roll off to -60db.  I think, ultimately it is important to know the benefits and trade-offs to each variation.

[dwk]

Interesting results. There was some talk on diyaudio on how to do this with a Behringer DCX that I've been meaning to play with, but haven't gotten around to it.  Although the deqx or soundeasy would make this easier, this approach is quite feasible with standard IIR filters, as far as I can tell.

[ekovalsky]

That's interesting.  Once you get into digital crossovers, the possibilities are endless.  I've been having good luck with Chebychev crossovers over Bessel and Butterworth, and I have to feel sorry for those poor speaker designers who have to forever tinker with passive crossovers
 
http://www.audioholics.com/techtips/audioprinciples/loudspeakers/speakerfilterscrossovers.php

Agreed!  I haven't yet told Carl M. or Harry P. that the very high quality passive crossovers are being outperformed by a DSP solution programmed by an amateur