Sub Ray 4 A electric guitar pickup is actually much like an energetic mike coil. For many years, vibrant microphones have been wired with the voice coil attached with the primary of the microphone's transformer, and maybe not called to ground (‘floating'). The microphone's event is usually connected to the wire shield, which will be linked to the mike amplifier's surface (see Rane's website for more discussion).
By and big, energetic microphones are very calm products as a result of the mix of transformer isolation and healthy, floating transmission lines all through, as well as protected, humbucking coils.
Therefore why not instruments? Guitars are notoriously overwhelmed by noise. Humbucking pickups are only an incomplete (though essential!) solution. The most obvious alternative is always to move practicing the guitar collection to a balanced production, being a microphone. A similar idea was printed this 2001 patent program like this Sub Ray 4?