A guitar pickup, also known as a transducer, is an electromagnetic device that produces the distinctive sound of electric guitars. It creates a magnetic field around itself, “picks up” vibrations of the steel or nickel guitar strings as they interrupt the magnetic field, and converts them to an electrical signal using the principle of magnetic induction. This signal is then sent to a guitar amplifier, where it is amplified and converted into audible sound. Guitar pickups are also used in acoustic guitars to produce louder volumes than natural sound-box amplification can provide.
A pickup’s structure is straightforward. It’s made up of a thin rectangular magnet wrapped around a bobbin made up of thousands of turns of extremely fine copper electrical wire. A single coil-wrapped magnet can span all six strings of a guitar, or each string can have its own magnet. These magnets are screwed into the guitar body beneath the strings, with the magnetized surface pointing upward.
A guitar can have a single pickup or multiple pickups in various locations around the neck, bridge, and pickguard. The sound of a string changes as it travels down the length of the string; for example, a bridge position produces a clear bright sound, whereas a neck position produces a softer sound. Each pickup has its own distinct sound, which can be changed adjusting the pickup’s height in relation to the string. A layered sound is created using different pickup configurations or combinations. Variations in magnet type, magnet strength, wire size, and number of turns of the coil all affect sound.
There are many different types of guitar pickups on the market. Magnetic pickups, which are used in the majority of electric guitars, are divided into two types: single coil, which uses a single coil magnet for each string, and double coil, or Humbucker, which uses two coiled magnets with opposite polarity. Single coil guitar pickups were used on Stratocaster guitars from 1954 to 1979. Seth Lover, a Gibson engineer, created humbuckers in 1955 to cancel out unwanted “hum” sounds from nearelectrical wires, lighting, or appliances, which single coils tend to pick up in addition to string vibrations. Many modern guitars have both single coil and humbucker pickups.
Optical pickups detect when a light beam is interrupted the string. In 1969, Ron Hoag, the inventor of this pickup, debuted an optical pickup guitar at the NAMM Show in Chicago, which was the first of its kind. Parker Fly and Godin guitars feature Piezo electro-acoustic pickups, which use crystals to detect pressure changes.
Guitar pickups differ in terms of type and quality. Musicians typically use the ones that are best suited to their particular musical sound, or mix and match different ones to achieve the desired sound.