Quasimidi Drum Machine A guitar pickup is essentially just like a dynamic microphone coil. For many years, dynamic microphones have been wired with the voice coil attached to the principal of the microphone's transformer, and not introduced to soil (‘floating'). The microphone's case is normally connected to the wire shield, which will be connected to the microphone amplifier's floor (see Rane's site for more discussion).
By and big, vibrant microphones are very calm units consequently of the mixture of transformer isolation and healthy, hanging sign lines through the duration of, along with shielded, humbucking coils.
So you will want to instruments? Guitars are notoriously affected by noise. Humbucking pickups are only an incomplete (though essential!) solution. The obvious answer is to move the guitar collection to a balanced output, just like a microphone. A similar thought was published that 2001 patent application like this Quasimidi Drum Machine?