Marshall Amp Cover A electric guitar pickup is basically much like a dynamic microphone coil. For many years, energetic microphones have been wired with the voice coil mounted on the primary of the microphone's transformer, and perhaps not introduced to ground (‘floating'). The microphone's event is typically linked to the wire guard, which is attached to the microphone amplifier's ground (see Rane's internet site for more discussion).
By and big, energetic microphones are very calm devices consequently of the mix of transformer isolation and healthy, flying sign lines throughout, as well as protected, humbucking coils.
Therefore why not guitars? Instruments are notoriously affected by noise. Humbucking pickups are only an incomplete (though important!) solution. The obvious option is always to move the guitar pickup to a balanced production, just like a microphone. The same strategy was published that 2001 patent application like this Marshall Amp Cover?