Fulltone Deja Vibe A guitar pickup is basically similar to a dynamic microphone coil. For many years, active microphones have already been wired with the voice coil attached with the primary of the microphone's transformer, and not recommended to ground (‘floating'). The microphone's case is normally attached to the wire shield, which can be linked to the microphone amplifier's soil (see Rane's site for more discussion).
By and large, powerful microphones are extremely quiet products consequently of the combination of transformer solitude and balanced, suspended indication lines throughout, as well as shielded, humbucking coils.
So why don't you guitars? Instruments are once overwhelmed by noise. Humbucking pickups are just a partial (though important!) solution. The most obvious answer would be to float the guitar pickup to a healthy result, being a microphone. A similar thought was printed this 2001 patent application such as Fulltone Deja Vibe?