Bass Strings For Fretless A electric guitar pickup is basically just like a dynamic mike coil. For many years, vibrant microphones have already been wired with the style coil mounted on the principal of the microphone's transformer, and perhaps not introduced to soil (‘floating'). The microphone's situation is typically connected to the cable shield, which can be connected to the mike amplifier's floor (see Rane's site for more discussion).
By and big, active microphones are very calm products as a result of the mix of transformer isolation and balanced, suspended transmission lines throughout, in addition to shielded, humbucking coils.
So why don't you instruments? Instruments are notoriously plagued by noise. Humbucking pickups are only a partial (though essential!) solution. Well-known answer is to float your guitar pickup to a healthy result, just like a microphone. An identical thought was published that 2001 patent application such as Bass Strings For Fretless?