How to site your equipment

Hey there, the following is the text from the owners manual: Power supplies and amplifiers need to be kept at a reasonable distance from other equipment or their transformer will interfer with it, and possibly cause hum audible from the loudspeakers. 300mm (12inches) is the minimum recommended distance and that allowed by the standard interconnect lead is the maximum.
How to do that in a Fraim, other than having an empty shelv?

Regards from Denmark
FE