it sounds like your basic saw, with a bit of attack, and slightly increasing vibrato as the legato of the synth plays out.
theres also some warm distortion on it. theres a bit of lfo before the distortion unit though. most likely on pwn or phase to my ears.
so create a saw lead, with 3 oscilators all saw, detune each oscilator a bit with a very slow lfo. also try modulating the lfo on the pwn and phase of thes three oscilators.
add a little attack, and more decay than sustain in the volume envelope, and try messing around with your filter envelope to get the distinct "thudding sound" when every not hits.
now you want to have the note play out flat at the beginning, and slowly modulate near the end. I can tell you you will need a synth with ccmod mididata support, so you can sequence in the distinct vibrato that only arises on the tail of certain notes
what may or may not be the overarching "sound" of this synth those is a pre-distortion very slow lfo attacked to a resonancey notch filter, moving up and down very little amounts in the midrange somewhere. by modulating this, you get that movement out of the synth
then, put distortion onto this whole thing, and you should have a sound pretty close.
on top of the synth is a bit of reveerb, and if im hearing correctly slight bit of delay
