The Vocal Fry
The "vocal fry" register is the raspy or creaky sound produced when you try to go low with your vocal chords. The term "fry" comes because it reminds some of the sound of sizzling bacon. Lots of discussion on whether it is an affectation, some consider it gimmicky or annoying. There is also some concern that it harms your chords if overdone.
Whatever your thoughts, DeAnna does the vocal fry thing both subtly and beautifully. She never overuses it, just enough to give variety to her vocal inflections.
Here is a passage where she treats her voice truly like a musical instrument. In the lead-in to a verse on her live cover of "All I Want", she uses a subtle vocal fry both to create a percussive affect and crack an emotion. It goes by real quick at the beginning so listen carefully:
After the fry break, DeAnna transitions into an ultra-smooth delivery, a transcendent four seconds of vocalese, perfectly matched to the backing acoustic strum.
Breaking that vocal down, the fry part is the short hiccup at the beginning of the waveform, where she intones a vocal fry on the "I" in "I can die a happy woman, I'm sure".
Magnifying that beginning part, its actually only a fraction of a second where her voice creates three staccato spikes, each trailing off with a nice tone. That's enough to give her voice a both haunting and sensual feel to the rest of the verse.
DeAnna doesn't go overboard with this technique, but if you listen carefully to her songs you will occasionally find subtle hints of her fry sprinkled around vocal breaks.
It's amazing how such a subtle effect -- which DeAnna absolutely nailed in a live setting -- can be so captivating. That's why the human voice is so fascinating to me; I don't know how these singers can do it with such precision, but its fun to try to figure it out !
And thanks to the @vocalfrier at WFMU for exposing singers with interesting tones to his radio show listeners. I wasn't all that familiar with the vocal fry technique until Dan B mentioned it.