Microphone Dynamic Range Definition A guitar pickup is basically much like a powerful microphone coil. For many years, powerful microphones have now been wired with the voice coil attached with the principal of the microphone's transformer, and perhaps not referenced to surface (‘floating'). The microphone's event is typically connected to the cable shield, which will be attached to the mike amplifier's floor (see Rane's internet site for more discussion).
By and big, active microphones are extremely quiet devices consequently of the mixture of transformer solitude and healthy, flying transmission lines for the duration of, in addition to guarded, humbucking coils.
Therefore why not instruments? Instruments are notoriously affected by noise. Humbucking pickups are only an incomplete (though essential!) solution. Well-known option is to float practicing the guitar collection to a balanced output, being a microphone. The same thought was published this 2001 patent application like this Microphone Dynamic Range Definition?