Simon has 30 years’ experience at Abbey Road. Equally at home with vintage analogue and cutting-edge digital equipment, he masters both stereo and 5.1 surround projects, and has been involved with many live music projects over the years. Simon works in any musical genre from rock and pop to symphonic orchestral soundtracks and from contemporary jazz to vocal and choral albums. Translating an artist’s wishes into musical reality always takes a wide variety of skills and a fair amount of patience. Like his Abbey Road colleagues, Simon believes passionately in going the extra mile to give the client exactly what they want, using his wealth of knowledge and musical experience to produce great-sounding masters.

Simon has mastered the work of some of the world's best known names in pop, rock and classical music, including 5.1 surround projects for The Beatles (Yellow Submarine), Paul McCartney (Under The Staircase – for Spotify), Take That (Wonderland Tour), Depeche Mode (Live in Berlin), Robbie Williams, Wings (Rockshow), Sigur Ros (Heima) and numerous albums for the Choir of King's College, Cambridge.

Simon is also in demand for the soundtrack albums to many Hollywood blockbusters, including All The Money In The World, Wonder Park, The Hobbit (Parts 2 and 3), Into the Woods, Les Miserables, Skyfall, Spectre, The King's Speech and the 5.1 audio versions for Harry Potter and the Deathly Hallows (Parts 1 and 2). Since working on Howard Shore's scores to The Hobbit, Simon has mastered the complete back catalogue of Shore's film scores, including Naked Lunch, Maps to the Stars and Spotlight. Recent TV soundtracks have included Our Planet for Netflix, Dr Who (Series 11) and Broadchurch.

More recently, he has mastered the first two albums for Carly Paoli, one of the UK’s brightest young sopranos, and he works frequently with the a cappella group VOCES8.

Simon is one of the world's leading audio restoration and remastering engineers. He was responsible for all of the audio restoration on the Grammy Award-winning The Beatles Album Remasters (2009). Other restoration projects have included Wings' Band on the Run and Ram albums (both Grammy nominated, with Band on the Run winning the Historical category in 2012). In 2017, Simon worked on the 50th Anniversary reissue of Sgt. Pepper's Lonely Hearts Club Band and is involved in all of The Beatles archive projects produced at Abbey Road. In 2020 Simon has again been nominated for a Grammy in the Historical category for Bobbie Gentry: The Girl From Chickasaw County – The Complete Capitol Masters, released in 2018.

Simon won a Gramophone Award in 2007 for the CD remaster of the Lyrita catalogue of music by British composers. He was part of the Abbey Road team who remastered the complete studio recordings of Maria Callas, released in 2014 to great acclaim. For EMI and Warner, he has remastered and restored countless archive tapes from the LP era, both classical and pop.