The grinding, heavy riff tone that opens Whole Lotta Love. Jimmy Page's Les Paul through a cranked Marshall Super Lead produces a thick, aggressive overdrive with singing sustain. The riff is played in standard tuning with the neck pickup for extra fatness, then the solo sections use the bridge pickup for a more cutting tone. Page also used a theremin and backwards echo for the psychedelic middle section.
AC/DC guitar tone settings for both eras; the SG, the Marshall, amp dials by era, and how to approximate it on Helix and Quad Cortex.
Both run real Marshall circuits in 20-watt format, but a JTM45 with KT66s and a 1959 Plexi with EL34s are different amps. Here's which Studio you should buy.
Both are 20-watt small-format Marshalls with the original Marshall circuits inside, but a 1959 Plexi and an 800 are different amps. Here's which Studio you actually want.