During this time he first worked with Greg Walsh (who would later go on to produce Heaven 17 and Tina Turner among others), whom Guthrie asked to join his FOH production team for the live performances of Pink Floyd's The Wall in 1980 and 1981.
[4] In addition, Guthrie is also credited with suggesting Jon Carin as a keyboard player for Roger Waters' touring band[5] (making Carin one of a select group of people to have played with both Waters and Gilmour, and an incarnation of Pink Floyd), and arranged for Kashmir lead vocalist and guitarist Kasper Eistrup to audition for the same tour (as documented in the film Rocket Brothers), as well as introducing vocalist Rachel Brennock (his then-girlfriend,[6] who used the stage name Rachel Fury) to Pink Floyd,[7] she joined the touring band from 1987 to 1989.
His initial producer credits would be for singer-songwriter Arlen Greene (co-producing the song "The Jazz Pianist" in 1976) and Fury (their only known single "Miss Demeanor/Stay on Your Feet" in 1977).
Guthrie's connection with GTO Records landed him engineering and production duties on the second and third albums for The Movies (Double A and Bullets Through The Barrier); followed by work with Runner (producing their only release, which made the Billboard Top 100).
Guthrie's initial involvement with Pink Floyd was to last nearly five years; in addition to engineering and co-production duties on The Wall, he also served as the Sound Mixer (supervising the Front of House engineering team) on most of the performances of The Wall live as well as actual recording of some of the performances (he would later provide the mix and production for the release Is There Anybody Out There?
In 1986 Guthrie emigrated to the United States, first residing in Los Angeles where he and his business manager/partner Larry Belling owned and operated Slippery Studios, a recording facility specifically geared towards sessions for film.
In the 1980s, Guthrie would produce a number of other releases, including Heatwave's fourth album Candles (co-produced with lead singer Johnnie Wilder, Jr.), Queensrÿche's major-label debut The Warning, Ambrosia's concept album Road Island (the final release of the David Pack era), and three tracks on The Boomtown Rats' In the Long Grass.
He would also work as an engineer on various releases, such as Kate Bush's Hounds of Love (all orchestral sessions) and The Dream Academy's Remembrance Days; as well as contributing miscellaneous music and sound design for films such as Lethal Weapon, The Dead Zone and Lifeforce.
[13] Guthrie's primary responsibility was (as it is to this day) to serve as one of the final authorities on the audio quality of Pink Floyd and Floyd-related releases.
")[15] In 2002, Guthrie was selected by the band to engineer the 30th Anniversary reissue of The Dark Side of the Moon in the SACD format, providing the mix and mastering for 5.1 Surround Sound.
2012 would see Guthrie returning to producing with The Dreamer's Machine, the debut album by singer-songwriter James Carrington, which he co-produced and mixed.
In 2014 Guthrie was invited to be the Guest of Honour for Princeton University's Pink Floyd: Sight, Sound and Structure academic conference – which took place 10–14 April – sponsoring a 5.1 demonstration of The Dark Side of the Moon and Wish You Were Here albums and the world premiere of the Surround Sound mix of Roger Waters' 1992 release Amused to Death, as well as delivering a keynote speech on his work with Pink Floyd in addition to his insights regarding the roles of production and engineering in recorded music.
In 2018, Guthrie and Plante undertook a project to remaster the entire studio catalogue for Kate Bush, to be released in a series of boxsets as well as single discs.