Modern Hard Rock Bands A guitar pickup is basically much like a dynamic microphone coil. For decades, dynamic microphones have been wired with the voice coil mounted on the principal of the microphone's transformer, and not recommended to ground (‘floating'). The microphone's case is normally linked to the wire guard, which is linked to the mike amplifier's floor (see Rane's site for more discussion).
By and big, energetic microphones are very quiet products consequently of the mix of transformer isolation and healthy, hanging sign lines for the duration of, as well as guarded, humbucking coils.
Therefore why don't you guitars? Guitars are once affected by noise. Humbucking pickups are just an incomplete (though important!) solution. Well-known solution would be to move the guitar pickup to a balanced output, being a microphone. The same thought was printed that 2001 patent application such as Modern Hard Rock Bands?