On active filtering

[CeramicMan]

Do most people feel the Linkwitz-Riley active filter design presented there is the best? I've been very impressed with it so far and can't see why people use other arrangements; its not especially complicated to build the Linkwitz-Riley arrangement.

It depends on what you want to use the filter for.

E.g.: if you want the averaged response not to have a 3dB dip at the crossover frequency, or the slope needs to be sharper then a Butterworth might be more appropriate.

 

[SY]

The filter type is only part of the equation. The first order of business (bad pun) is to determine what the final acoustical transfer function is. If you then know what the driver transfer function is, it's pretty easy to determine what the electrical filter has to do to get to the overall acoustic target.

The chances that using, say, a 4th order Linkwitz-Reilly filter will get you a 4th order Linkwitz-Reilly crossover is close to zero.

 

[CeramicMan]

Well... one could of course have a speaker that has a perfectly flat response already... It would be a shame to filter it