www.youtube.com/watch?v=vC9Qh709gas
www.youtube.com/watch?v=VGbFB91eM34
Following a series of posts to PHYS-L, I have been entertaining myself (and amusing my physics of sound students) by learning to sing harmonic overtones (two notes at once). The relevant videos are listed above; the first features Anna Maria Hefele, a trained singer specializing on overtones with astoundingly flexible and near-complete independent control over both the fundamental and overtone selection. Miroslav Grosser, the gentleman in the second video, shows how anyone can better isolate and lock in on the natural overtones we continuously produce with our voices by focusing on sliding back and forth between vowels while singing a constant pitch. The effect is a wonderfully fun and offbeat application of physics, and I have been trying to learn to better isolate and project a very few overtones metallically howling along with Springsteen's Darkness on the Edge of Town CD in my car— Springsteen uses lots of...