Another graphically minimalistic plugin from Inear with a resolutely glitch/ electronica agenda, Rmpx4 takes three crossfadable pairs of processors - muiltimode filters, pitchshifters and delays - and modulates the hell out of them.
The resonant filters offer high-, low- and band-pass modes; the pitchshifters give two octaves of shift in either direction and feature adjustable buffer lengths; and the delays can be placed pre-filter or post-pitchshifter.
Two envelope followers and four LFOs supply the modulation signals, which can be multiplied, inverted and mixed; and the Mix module itself can be modulated, too.
While Inear's GUI house style could never be described as user-friendly, Rmpx4 is much easier to use than it looks - and positively intuitive compared to Bowecho.
Like its stablemate, though, it makes for a wildly entertaining sound-design toolbox from which simple or complex effects can be coaxed in minutes (even if they're not always pleasant). And once again, the price is most certainly right.