The latest plugin from the de la Mancha workshops is a freeware, 3-band splitter called fr33some. You can use it to define 3 frequency ranges for low, mid and high frequencies, and output each band to a different stereo output, for individual processing.
· 3 band splitter
· Split stereo input into 3 stereo outputs for low, mid and high frequencies
· 3 frequency ranges are user definable using non-linear knobs
· Zero phasing band splits using inversion rather than crossover
· free version of the splitter used in thr33some