Yamaha C7 Piano A guitar pickup is actually just like an energetic mike coil. For many years, energetic microphones have already been sent with the style coil attached to the primary of the microphone's transformer, and maybe not recommended to ground (‘floating'). The microphone's case is typically linked to the cable guard, which will be attached to the microphone amplifier's floor (see Rane's web site for more discussion).
By and big, powerful microphones are very calm devices consequently of the mixture of transformer solitude and healthy, hanging sign lines through the duration of, along with guarded, humbucking coils.
Therefore why don't you guitars? Instruments are notoriously affected by noise. Humbucking pickups are only a partial (though crucial!) solution. The most obvious solution is to float your guitar pickup to a healthy productivity, being a microphone. A similar idea was published this 2001 patent request such as Yamaha C7 Piano?