When listening back to recordings of the genuine amplifier (1984 JCM 800) and the Kemper, I noticed that the tonal differences were so minute that the practicality of using my JCM 800 profile far outweighed using the real thing for the majority of work I do today.
I profiled this amplifier close to full volume with the preamp gain on 10 for the High Gain (HG) profile with an SM57 on-axis (1960 4×12). This also works brilliantly with a Tube Screamer to push the amplifier into a tight modern-metal tone.
The second profile was similarly recorded at close to full volume with the preamp gain set around 7 (MG). This was captured with an SM57 slightly off-axis (1960 4×12). I feel this particular profile is the best all-round rock profile in my collection and most faithfully captures the essence of this particular JCM 800 – This is my go-to rock tone!