It's been a while since I used this driver. I seem to recall I was ok with 3-4mm each way. I used it with several horns, some with and some without a phase plug.
It says it right there on the spec page: B&C Speakers : 2.5mm
Compression you get due to heat buildup. So the amount and time of power you poor into it is the determining factor or here, not only the excursion.
Compression you get due to heat buildup. So the amount and time of power you poor into it is the determining factor or here, not only the excursion.