Today, the New York Times picked up on the trend (described as the "low, creaky vibrations" that come when you allow your voice to slide down to its lowest possible scale), which they say is just another example of young women getting "ahead of the linguistic currrrve," as with "uptalk," invented slang words, and the ubiquitous filler, "like":
The idea that young women serve as incubators of vocal trends for the culture at large has longstanding roots in linguistics. As Paris is to fashion, the thinking goes, so are young women to linguistic innovation.
"It's generally pretty well known that if you identify a sound change in progress, then young people will be leading old people," said Mark Liberman, a linguist at the University of Pennsylvania, "and women tend to be maybe half a generation ahead of males on average."
Mark Liberman! We've heard from you before, Mark Liberman. You wrote that fascinating piece about NYT executive editor Jill Abramson's voice back in October! What did you say about Jill Abramson's voice again, Mark Liberman?
I grew up here in Manhattan and uh
The ratio between the fundamental and the infrasonic modulation is variable - it seems to be more like 8-to-1 towards the end of this sample - but the general pattern remains the same. Her long/low/loud phrase endings also often shift into "vocal fry", which is a kind of chaotic oscillation; thus the pronunciation of the second syllable of "schoolkid" in the passage quoted above.
That's a lot of indecipherable linguist speech, but I did recognize one familiar phrase: Vocal fry. Jill Abramson, executive editurrrrrr, is ahead of that currrrve after all.