FIR linear phase crossover

Hi all,

I’m trying to build a 2 band linear phase crossover using the Juce FIR filters, but I’m not sure how to go about creating the highpass version. Any general tips would be greatly appreciated, but in particular I’m wondering:

  1. Is there a simple way to transform lowpass coefficients into matching highpass?

  2. I have tried subtracting the lowpass from a delayed dry signal to get the highpass, but that doesn’t seem to produce usable results. Perhaps I’m doing it wrong. Should this be possible?