Absolutely fascinating, and slightly terrifying! I've heard a sound like this in Portland, OR several times over the past couple years, on the second occurrence my neighbor managed to get a video of it [1].
It sounded like absolutely nothing I've heard in my life, like a giant didgeridoo but so powerful you could feel the vibration in your chest. Many others in my neighborhood heard it too, as referenced by this Reddit thread [2].
Have thought about it for a long time and no explanation makes sense, I still get shivers listening to the youtube video; Play it plugged into a sound system for full effect!
It sounded like absolutely nothing I've heard in my life, like a giant didgeridoo but so powerful you could feel the vibration in your chest. Many others in my neighborhood heard it too, as referenced by this Reddit thread [2].
Have thought about it for a long time and no explanation makes sense, I still get shivers listening to the youtube video; Play it plugged into a sound system for full effect!
1. https://www.youtube.com/watch?v=MJbH8jd8dz0 2. https://www.reddit.com/r/Portland/comments/3gf6qf/what_was_t...