While "Pyromania" contained traces of Def Leppard's original traditional heavy metal sound found on their first two albums, "Hysteria" removed them in favour of the latest sonic technology available at the time (best displayed on "Rocket", "Love Bites", "Excitable", and "Gods of War"). As with "Pyromania", every song was recorded by every member in the studio separately instead of the whole band. The multiple vocal harmonies were enhanced by Lange's techniques, even pitching background vocals on all tracks. Guitar parts were now focused more on emphasising melody than hard rock's more basic and clichéd riffs. The band used the Rockman amplifier, developed by guitarist Tom Scholz from the rock band Boston, to record the album. Engineer Mike Shipley described the Rockman as "a shitty little box" with "a godawful sound" that "had no real balls to it", but it was used because the other amplifiers used had an excessively "crunchy" sound ill-suited to layering guitars and which Lange did not think was "commercial" enough.