Electric Guitar Kid Size A guitar pickup is basically just like a vibrant microphone coil. For decades, dynamic microphones have been wired with the style coil attached to the primary of the microphone's transformer, and not recommended to soil (‘floating'). The microphone's case is usually connected to the cable shield, which can be connected to the microphone amplifier's ground (see Rane's website for more discussion).
By and large, dynamic microphones are very quiet units consequently of the combination of transformer isolation and healthy, floating sign lines for the duration of, along with guarded, humbucking coils.
Therefore why don't you instruments? Guitars are once affected by noise. Humbucking pickups are only a partial (though important!) solution. The obvious answer is to float practicing the guitar pickup to a healthy production, being a microphone. An identical idea was printed this 2001 patent request such as Electric Guitar Kid Size?