In article , Chris Morriss
wrote:

This is the crux of the issue. To get a flat amplitude response from an
even order filter, the crossover frequency should be at the -6dB point,

Not quite. The only general requirement would be that the vector sum adds
up to the 0dB level. If you allow the components to be in quadrature, for
example, this can occur if they cross at -3dB.

A problem here is that there is often an ambiguity in discussions due to
the coherent effects of the way the radiation pattern is affected by phase,
and the mean (space-averaged) power around a room, and on axis.

Ideally, you'd want to know the directional and amplitude/phase properties
of the speakers, and the acoustics of the room, and the choice of listening
location. Lacking these, you end up with having to choose a set of
assumptions.

Slainte,

Jim

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