Newb, need help mod'ing an ESP constant Q xover design

[jmartinson]

Hello,

I wanted to build the ESP "24 dB/Octave 2/3-Way Linkwitz-Riley Electronic Crossover " primarily b/c of the correct phase alignment that a lot of other crossovers supposedly don't offer.

That project is shown here:
http://sound.westhost.com/project09.htm

I just need a single channel low pass cirtcuit to feed into my subwoofer amplifier though, not a 2 or 3 way stereo version.

Can I just take the bottom half of the top cirtcuit (left channel) in this image: http://sound.westhost.com/p09_fig1b.gif

and leave out the part of the circuit that appears to be dedicated to the high pass part... leaving out everything between the first 33nF cap on the left and the "L Mid+High" output on the right? Or will that throw something off with the low pass part of the circuit?

Or does anyone know of another constant Q/phase coherent active xover design that just implements a low pass filter?

A friend loaned me his tech-school electronics book, but it doesn't talk at all about crossovers other than passive filters, and I have only a marginal electronics background myself, so I am a little lost here.

Any information or pointers to good reading material would be greatly appreciated!

Thanks,
Jacob

[jmartinson]

Yikes... There is a part of the text I must have overlooked, where it says the high and low pass sections must be perfectly matched otherwise there will be severe problems.

In any event, does anyone know of a similar quality design but that just implements a low pass filter?

Thanks!
-Jacob