I’m not sure why, to be honest, but this year’s edition of The Voice has been the most emotionally satisfying and vocally impressive yet. The contestants have unusually compelling voices, and stories, this season, which is a large part of it – but the judges, too, seem to be having an especially good time this year. And based on the promos, tonight’s the night Pharrell , Christina Aguilera and especially Adam Levine tease fellow judge Blake Shelton about his “girlfriend,” sometime judge (and, this cycle, Shelton’s guest mentor for his team of singers) Gwen Stefani.