I don't know if I'm hearing the right sound, but it sounds like a sawwave where they've used an EQ and cut away a lot of the midrange, and then boosted the 2-3 kHz region. And then some highpass of course.
it's possible but adding a distortion unit to a sine will achieve almost the same outcome with nowhere near the hassle - i.e. it sounds like an over-modulated 808 sine kick