A pickup (English: pickup) is a transducer that causes mechanical vibrations. It is commonly found on stringed instruments, such as electric guitars, electric basses, or electric violins, to convert musical sounds into electronic signals.
Magnetic pickups are constructed with a bar-shaped permanent magnet (such as Alnico) as the center, around which an enamelled copper coil of thousands of turns is wound. It is typically mounted to the body of an instrument, but can also be attached to the bridge, neck, or pickguard, such as many jazz electric guitars and double basses. When the nearby soft magnetic strings vibrate, modulation occurs, changing the magnetic flux of the coil, causing the coil to generate alternating current due to electromagnetic induction. The signal is then sent to an amplifier or recording instrument via wires. There may also be an internal preamplifier between the pickup and the cable. Generally speaking, a pickup can be said to be an application of the concept of a magnetic circuit, in which the reluctance generated by the permanent magnet will change with the vibration of the strings.
An electric guitar usually has multiple magnetic pickups. The combination of pickups is called "pickup system" or "pickup device". Generally, "single" (S) form coil pickups and "double" (H) form double coil pickups are arranged in order from the bridge to the neck. Common pickup systems include:
Single-single (S-S), such as: Fender Telecaster
Single-single-single (S-S-S), such as: Fender Stratocaster
Single-single-double (S-S-H), such as: Peavey Raptor EXP
Double-single-double (H-S-H), such as: Superstrats