Questions about 3-way crossover

[Pedroga]

I'm going to use a 3-way crossover board (Where I will connect the sub woofer (bass), Mid-ranger (Mid) and the tweeter (tremble)) my question is:
All speakers have exactly 4 Ohms of impedance and I will connect them all to the crossover board, so can I connect a 4 ohm amp to the crossover board?

 

[rayma]

Yes. The drivers only present 4 ohms to the amplifier within their individual working ranges.
Outside of each range, the crossover impedance rises, so you don't get three 4 ohms in parallel.