Since Black Sabbath’s self-titled debut album in 1970, metal music has been on a quest for greater heaviness. Numerous advances in music production over the last fifty years, such as extended layering of guitar sounds, drum enhancement and digital editing, were significant facilitators that enabled hyperreal performances and powerful, ‘heavy’ sounds.

This three-year-long AHRC-funded project (September 2020 to August 2023) examines how leading metal producers specialising in different subgenres define heaviness, and how they process and control the constituent aspects of heaviness during the mixing of recordings. It analyses the producers’ understandings of heaviness, their individual approaches, and how the characteristics of the musical material influence their mixing decisions.

To learn how internationally renowned professionals create heaviness in different subgenres of metal, the researchers – Jan Herbst (Principal Investigator) and Mark Mynett (Co-Investigator) – document how the producers mix a song comprising parts emblematic of various subgenres of metal. All their steps are documented via screen-capture, videos showing the use of outboard equipment, video-recorded interviews and the files of each producers’ mixing project.

All material including the raw recordings, the mix project files, the edited videos of the producers’ sessions and interviews are available on the project’s website. These resources provide authentic, first-hand documentation demonstrating the crucial decision-making processes and the techniques involved in high-end metal music production.

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