This is a snippet from "Ride across the river", from Dire Straits. Notice the distorted guitar sound at the beginning; is that sound a result of two close notes (e.g. a semi-tone or tone apart) played together, just a distortion pedal or both?

[Snippet (starting at 2min40s of the full soundtrack)][1]

P.S. I'm not quite asking for the exact notes, since I'll not try to play that particular song. I'm just interested in how to obtain this "growly" effect.

  [1]: https://clyp.it/w4pfkibe