Anti K, using a lowmid can be rewarding, but it is pretty difficult to setup correctly, especially the crossover with the woofer(s).
3-ways are specially tricky to get right when it comes to phase tracking.
Here are a few points to consider when choosing such a driver:
- choose the diameter based on the directivity and crossover frequency with the horn
- choose the highest sensitivity driver that still has enough excursion to go down to the woofer crossover at your target SPL and distortion.
- choose a cone that does not show any major breakup artifacts up to 1/2 oct above your horn crossover (more or less, depending on the slope there)
- choose a good modern motor *or*, better still, use a current drive amp (transconductance) to reduce distortion in the mids