Kawai Digital Piano Pn80 A guitar collection is basically just like an energetic mike coil. For decades, active microphones have been sent with the voice coil attached with the principal of the microphone's transformer, and not recommended to soil (‘floating'). The microphone's case is typically attached to the wire shield, that will be connected to the microphone amplifier's floor (see Rane's site for more discussion).
By and big, energetic microphones are very quiet products consequently of the combination of transformer isolation and balanced, hanging indication lines throughout, as well as guarded, humbucking coils.
Therefore why not instruments? Guitars are once plagued by noise. Humbucking pickups are merely a partial (though essential!) solution. Well-known solution would be to float the guitar pickup to a healthy productivity, just like a microphone. An identical strategy was published that 2001 patent program such as Kawai Digital Piano Pn80?