Ultimate Guitar Free A electric guitar pickup is actually just like a powerful microphone coil. For many years, energetic microphones have now been wired with the style coil attached to the primary of the microphone's transformer, and not recommended to floor (‘floating'). The microphone's event is typically linked to the cable guard, which will be attached to the microphone amplifier's ground (see Rane's site for more discussion).
By and big, energetic microphones are very calm devices consequently of the combination of transformer isolation and healthy, suspended transmission lines throughout, in addition to shielded, humbucking coils.
Therefore why not instruments? Instruments are once plagued by noise. Humbucking pickups are only a partial (though important!) solution. The obvious solution would be to float the guitar pickup to a healthy output, just like a microphone. An identical strategy was published this 2001 patent request like this Ultimate Guitar Free?