"Adios," the title track from Glen Campbell's forthcoming farewell album, is a poignant goodbye. Readers can press play above to hear the track.

After being diagnosed with Alzheimer's disease in 2011, Campbell embarked on a final tour; he also got into the studio with his longtime banjo player, Carl Jackson, and others to record one last record. Its title track was written by Jimmy Webb, who penned a number of Campbell's classic songs, including "Wichita Lineman," among others. "Adios" was originally a Top 10 hit for Linda Ronstadt on the adult contemporary charts in 1990.

"Glen and I used to play that song all the time. We played it in dressing rooms, hotels, we played it over at his house, we played it at my house. He always loved that song," Webb says of the song in an interview with Rolling Stone. He adds that Campbell's rendition of "Adios" is "extraordinary" and made him cry when he first heard it.

Jackson, meanwhile, says that he paid special attention when recording "Adios" with Campbell.

"It was just one of the songs that Glen loved and that I loved. I've always been a fan of that since Linda did it. And there's not a better writer than Jimmy Webb," Jackson says. The song closes Campbell's final album; Jackson calls it "the perfect slot."

"It was something that Glen and [his wife] Kim wanted to do," Jackson adds, "and I'm honored that they put their trust in me to be able to get it done."

Adios is set for release on June 9 and is available for pre-order on Amazon and iTunes

Glen Campbell Through the Years