Daniel James Irving (born April 16, 1969), better known as Dan Druff, is a guitar technician and musician who has worked with various artists in the studio and on tours, including Queens of the Stone Age, Guns N' Roses, Tool, Sum 41, Wolfmother, The Distillers, Coheed and Cambria, Monster Magnet and Madrugada.^[1][2][3] Druff is best known for his work with Queens of the Stone Age, which saw him work as a technician on three studio albums and join the band for a stint as touring bassist. He has worked as a studio technician on over 30 albums throughout his career.^[3]

Druff was born in New Haven, Connecticut and formed the St. Louis rock band Shagnaps in 1991. The band consisted of Druff as guitarist and co-vocalist along with bassist and co-vocalist Otis London and drummer Tony Mack. The Shagnaps broke up in 1995, but played reunion shows in 1996 and 1998. Druff had a brief stint with the punk band Butt Trumpet in 1995, before abruptly quitting the band onstage at a New York City concert. He appears in the band's video for the song "I'm Ugly and I Don't Know Why."

Druff started working with Queens of the Stone Age on their 2000 album Rated R and subsequently worked on their follow-up album Songs for the Deaf.^[4] In early 2004, bassist Nick Oliveri was fired by frontman Josh Homme and replaced by Druff.^[4] Druff worked on the band's following album, Lullabies to Paralyze, as a technician and appears in the videos for "Little Sister" and "Long Slow Goodbye".^[5] He left Queens of the Stone Age in 2005 and later toured as a tech with Guns N' Roses on the Chinese Democracy Tour.^[6] In 2019, Druff worked as technician on Tool's Fear Inoculum album.