From Queenpedia.com

Reinhold Mack (aka Mack) is a German record producer and sound engineer, mostly known for his collaborations with Queen and E.L.O.

Selected discography

Albums produced or co-produced by Mack:

• Queen: The Game (1980)
• Queen: Flash Gordon (1980)
• Queen: Hot Space (1982)
• Queen: The Works (1984)
• Roger Taylor: Strange Frontier (1984)
• Freddie Mercury: Mr. Bad Guy (1985)
• Queen: A Kind Of Magic (1986)
• Heavy Pettin: Lettin Loose (1987; produced by Brian May and Mack)