The traditional approach to bi-amp/bi-wiring speakers is to connect the treble and bass to the same impedance tap at the amplifier output. Since the Blade is rated at 4Ω, you can connect both to a 4Ω tap.
You can also experiment by connecting both to 2Ω or 8Ω tap to see which sounds best without damaging the amplifier or speakers.
However, if the speaker treble and bass are connected to different impedance taps of the amplifier, the output levels of the high and low frequencies may be affected.