Next time you’re seeking a caffeine fix in Starbucks, keep your ears open for a song by J.R. Rhodes ’90. Hers is a haunting alto voice—with a throatiness and rich, emotional depth reminiscent of Joan Armatrading—and the song, in a minor key, “Your Pillow,” was the first single released from her album I Am, due out Nov. 3. A music major at Wesleyan and a singer/songwriter since then, Rhodes had released three albums previously: Elixir (2011), Afriqueen Stare (2003) and Songs of Angels (1999). The high-profile single placement, however, is something entirely new. “A career in music can definitely be…