John Huntington and his friends decided to test the reported phenomenon of infrasound (very low-frequency sounds) causing people to feel spooky chills and thrills, a phenomenon blamed for ghost sightings and reports of hauntings. They created a spook-house with a double-blind randomized infrasound generator and used surveys to check for a correlation between infrasound and creepy feelings. John exhaustively documented the experimental setup (and the setbacks encountered in getting things up and running), and the results. Spoiler alert: they didn't find a correlation.
We picked a 19 Hertz (Hz, or cycles per second) sine wave as our infrasound source, since that's the frequency Tandy and Lawrence had found in their initial investigation of a "haunted" space (see Part I of this series for details). For our initial tests last spring, we used an Audio Toolbox as our signal generator, and connected it up to our ancient Apogee P-10 subwoofer processor and a Crown K2 amp, which drove an Apogee AE-10 double 18" subwoofer (these units work just fine, but haven't been made in years.) We got the sound going, but after a minute or so, it would cut out. I figured out that the processor was apparently protecting the subs against the "bad" infrasound, and was cutting out. So, I bypassed the processor and its protection circuits, and (carefully) drove the subwoofers directly from the amp. This worked just fine, but I was a bit concerned about damaging the speakers themselves. Fortuitously, over the summer I managed to get for our department a massive, modern Meyer Sound 650-P powered subwoofer. And after some tests in late summer we determined that the unit could generate quite a bit of 19Hz without clipping, and we figured the level was pretty good because by the time we pushed the 650-P up to its limits, the effects of the infrasound would be obvious to anyone in the room, which wouldn't have been acceptable for our purposes.
Scientists drilled into the Chixclub crater in the Gulf of Mexico to learn more about the end of the mesozoic era. They learned more than they expected, reports Katherine Kornei in The New York Times. The first day of the Cenozoic was peppered with cataclysms. When the asteroid struck, it temporarily carved a hole 60 […]
Get over it! Despite the mockers and complainers, and even attempts to make it illegal to perambulate while looking at your own damned phone, science concludes that the risks of it are negligible. As part of the mandated study, the DOT conducted an in-depth review of written crash narratives in the city between 2014 and […]
Typically, marine photography is done in rich, saturated color — the better to show off the riot of life beneath the waves. But the photographer Christian Vizl has done it in high-contrast black and white, producing eerily intense ways of re-seeing marine life. You can see the work on his site, and in his new […]
Breaking into the big leagues as a project manager isn’t done overnight, but there are principles that anyone can learn, and they’re applicable to nearly any business. No matter what your field, if there are multiple teams working toward a common goal, you’re going to need a roadmap. The Project Management Professional Certification Training Suite […]
On the one hand, nostalgia is “a corruption of the historical impulse,” according to William Gibson. On the other hand, “Super Mario Bros.” will never not be cool. Luckily, there’s a way to satisfy that retro gaming while still keeping an eye on the future: The GameShell Kit. This thing is simultaneously the last handheld […]
The field of data analytics can get intimidating, even for business professionals who constantly rely on it. But at its heart, its purpose is to simplify. To take mounds of information and distill their insights into a single clear picture. Currently, the go-to software for painting that picture is Tableau. And if you want to […]