The French singers like that sound. Piaf for example. Buffy Saint Marie had it. It's a tremolo in the voice that trained vocalists and coaches attempt to eliminate. I like it better than Tom Wait's growl or even Dave Van Ronk's although I certainly acknowledge that they are and were great performers. And there's Louis Armstrong who ya' gotta' love.

It can be a traditional folk voice and effective as such. I loved hearing the late Bess Hawes, Alan Lomax's sister sing ballads and she had it.

It's not meant for conventional stage or concert singing.