Darker Than Blue has very amusing recollections from Ken Flegg, a former Marshall engineer, who accompanied the band on the trip to Japan in August 1972:

The third gig at the Budokan in Tokyo on the 17th August went well with no significant problems, other than the acoustics of the hall could have been better. Possible because of this the subject of the monitors came up again and Ian Gillan asked over the mic before Strange Kind of Woman: “Yeah everything up here please. A bit more monitor if you’ve got it.” Then Ritchie asks “Can I have everything louder than everything else?” which Ian Gillan repeats “Yeah, can he have everything louder than everything else.” This remained on the final master.

Read the whole thing in Darker Than Blue.