Guitar Pickups - Magnetic Pickups

Magnetic Pickups

A magnetic pickup consists of a permanent magnet with a core of material such as alnico or ceramic, wrapped with a coil of several thousand turns of fine enameled copper wire. The pickup is most often mounted on the body of the instrument, but can be attached to the bridge, neck and/or pickguard, as on many electro-acoustic archtop jazz guitars and string basses. The vibration of the nearby soft-magnetic strings modulates the magnetic flux linking the coil, thereby inducing an alternating current through the coil of wire. This signal is then carried to amplification or recording equipment via a cable. There may also be an internal preamplifier stage between the pickup and cable. More generally, the pickup operation can be described using the concept of a magnetic circuit, in which the motion of the string varies the magnetic reluctance in the circuit created by the permanent magnet.