2x12 Combo Amp A electric guitar pickup is basically just like a powerful mike coil. For many years, active microphones have now been sent with the style coil attached to the principal of the microphone's transformer, and perhaps not referenced to soil (‘floating'). The microphone's event is typically connected to the cable shield, which can be connected to the mike amplifier's ground (see Rane's internet site for more discussion).
By and big, dynamic microphones are very quiet units as a result of the mixture of transformer isolation and balanced, suspended transmission lines throughout, in addition to protected, humbucking coils.
So why don't you guitars? Instruments are notoriously overwhelmed by noise. Humbucking pickups are just an incomplete (though important!) solution. The most obvious option is to move the guitar collection to a healthy output, just like a microphone. The same idea was printed this 2001 patent application like this 2x12 Combo Amp?