Vortex Sound Research

Is it possible to get the same kind of FM/Phase modulation sounds you'd find in digital synths (like Ableton operator or seurm FM from B ) from an analog synth? If it is possible, do any exist? When I try to do FM with my analogs i get very different (out of tune) results compared to digital synth FM. I was told this is due to it not being linear FM or something like that? Id love to know more about this.