Led Zeppelin House Of The Holy Album A electric guitar pickup is basically similar to a dynamic microphone coil. For many years, active microphones have already been sent with the voice coil attached to the principal of the microphone's transformer, and not recommended to ground (‘floating'). The microphone's situation is normally connected to the cable guard, which can be linked to the mike amplifier's surface (see Rane's website for more discussion).
By and large, dynamic microphones are extremely calm units consequently of the combination of transformer isolation and healthy, suspended transmission lines for the duration of, along with protected, humbucking coils.
Therefore why not instruments? Instruments are notoriously plagued by noise. Humbucking pickups are only an incomplete (though important!) solution. The obvious option would be to float practicing the guitar collection to a balanced production, being a microphone. An identical strategy was printed that 2001 patent request such as Led Zeppelin House Of The Holy Album?