Leenia-- Yawning opens up the soft palate the same way. You just don't want too much so's you get a really covered tone. (Kindof woofy, like someone who doesn't know better trying to sing opera!)

Bill (and all), most people lose the high end with age. My kids would play this tone that I could not hear at all and said most folks over about 40 could not hear it. My daughter used to walk the halls of her high school and when she heard a monitor that was on standby after hours she would shut it off because it drove her nuts. Most teachers had no idea that they made noise when the screen went blank! Our generation is worse that previous ones a bit, but not as much as we think. Mostly we lost the high end earlier. (For me it was power tools and ramset tools)