From the department of hard-rain:
At breakfast time I was sitting by the house at Vanavara trading post (65 kilometres/40 miles south of the explosion), facing North. [...] I suddenly saw that directly to the North, over Onkoul's Tunguska road, the sky split in two and fire appeared high and wide over the forest (as Semenov showed, about 50 degrees up - expedition note). The split in the sky grew larger, and the entire Northern side was covered with fire. At that moment I became so hot that I couldn't bear it, as if my shirt was on fire; from the northern side, where the fire was, came strong heat. I wanted to tear off my shirt and throw it down, but then the sky shut closed, and a strong thump sounded, and I was thrown a few yards. I lost my senses for a moment, but then my wife ran out and led me to the house. After that such noise came, as if rocks were falling or cannons were firing, the earth shook, and when I was on the ground, I pressed my head down, fearing rocks would smash it. When the sky opened up, hot wind raced between the houses, like from cannons, which left traces in the ground like pathways, and it damaged some crops. Later we saw that many windows were shattered, and in the barn a part of the iron lock snapped.This is an eyewitness account of the Tunguska Event, a meteor or comet impact In Russia in June 1908. There are some very good indications that this is a true report. Notice that he heard a strong "thump" first, followed later by a massive explosive sound. This guy was 65 kilometres away from the explosion (which is scary when you consider that it was so hot that his shirt nearly caught fire). Sound travels faster through solid ground than through the air. The impact would've sent a very low frequency sound burst through the ground, reaching the person long before the actual sound did.