Blackstar Artisan 30 A best guitar collection is basically similar to a powerful microphone coil. For decades, energetic microphones have been sent with the voice coil attached with the primary of the microphone's transformer, and not introduced to ground (‘floating'). The microphone's case is typically linked to the cable guard, which can be connected to the microphone amplifier's floor (see Rane's site for more discussion).
By and big, powerful microphones are very quiet devices consequently of the mixture of transformer isolation and healthy, flying transmission lines all through, in addition to guarded, humbucking coils.
Therefore why don't you instruments? Instruments are once affected by noise. Humbucking pickups are only an incomplete (though essential!) solution. Well-known answer would be to move your guitar collection to a healthy productivity, just like a microphone. An identical thought was printed this 2001 patent request such as Blackstar Artisan 30?