His compositions included "Luckenbach, Texas (Back to the Basics of Love)", written with Chips Moman and recorded by Waylon Jennings; and "Love Me Like You Used To", co-written with Paul Davis and recorded by both Johnny Cash and Tanya Tucker.
Emmons was born in Corinth, Mississippi, and began performing when at high school.
He began playing keyboards in the house band at Hi Records around 1963, before moving to Chips Moman's American Sound Studio as a session musician.
Among the many records on which he played keyboards in the 1960s and 1970s were Elvis Presley's "Suspicious Minds" and "In the Ghetto", Dusty Springfield's "Son of a Preacher Man", Merrilee Rush's "Angel of the Morning", and Neil Diamond's "Sweet Caroline".
He also played on many of Willie Nelson's albums and toured internationally with The Highwaymen.