Heck yeah, that must have made a hell of a sound. I had a friend that lived at the bottom of a steep mountain in Hawaii and had a similar experience. The boulder coming down was significantly smaller, about the size of a VW Bug, but he said he and his buddies could hear it coming like a freight train. Thankfully it was stopped just short of the house by a thick stand of bamboo and a good sized tree. Otherwise it would have plowed straight through the room they were all hanging out in.