Martin Custom D Rosewood A best guitar pickup is actually just like a dynamic mike coil. For many years, active microphones have been wired with the voice coil mounted on the primary of the microphone's transformer, and maybe not called to floor (‘floating'). The microphone's event is normally linked to the cable guard, which can be linked to the mike amplifier's soil (see Rane's website for more discussion).
By and large, energetic microphones are extremely calm devices as a result of the mixture of transformer isolation and balanced, flying sign lines all through, as well as guarded, humbucking coils.
Therefore why not guitars? Guitars are once plagued by noise. Humbucking pickups are just an incomplete (though important!) solution. Well-known answer is to move your guitar pickup to a balanced result, just like a microphone. The same idea was published that 2001 patent application like this Martin Custom D Rosewood?