Editing Guitar (section)

====Pickups and electronics====
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{{Main|Pickup (music technology)}}
[[File:Stratocaster detail DSC06937.jpg|thumb|right|This [[Fender Stratocaster|Squier Stratocaster]] has features common to many electric guitars: multiple pickups, a [[Vibrato systems for guitar|vibrato bar]]/[[vibrato unit]], and volume and tone knobs.]]
[[Pickup (music technology)|Pickups]] are [[transducer]]s attached to a guitar that detect (or "pick up") string vibrations and convert the mechanical energy of the string into electrical energy. The resultant electrical signal can then be electronically [[amplifier|amplified]]. The most common type of pickup is [[electromagnetism|electromagnetic]] in design. These contain magnets that are within a coil, or coils, of copper wire. Such pickups are usually placed directly underneath the guitar strings. Electromagnetic pickups work on the same principles and in a similar manner to an [[electric generator]]. The vibration of the strings creates a small electric current in the coils surrounding the magnets. This signal current is carried to a [[guitar amplifier]] that drives a [[loudspeaker]].

Traditional electromagnetic pickups are either [[Single coil guitar pickup|single-coil]] or double-coil. Single-coil pickups are susceptible to noise induced by stray electromagnetic fields, usually mains-frequency (60 or 50&nbsp;hertz) hum. The introduction of the double-coil [[humbucker]] in the mid-1950s solved this problem through the use of two coils, one of which is wired in opposite polarity to cancel or "buck" stray fields.

The types and models of pickups used can greatly affect the tone of the guitar. Typically, humbuckers, which are two magnet-coil assemblies attached to each other, are traditionally associated with a heavier sound. Single-coil pickups, one magnet wrapped in copper wire, are used by guitarists seeking a brighter, twangier sound with greater dynamic range.

Modern pickups are tailored to the sound desired. A commonly applied approximation used in the selection of a pickup is that less wire (lower [[electrical impedance]]) gives a brighter sound, more wire gives a "fat" tone. Other options include specialized switching that produces coil-splitting, in/out of phase and other effects. Guitar circuits are either active, needing a battery to power their circuit, or, as in most cases, equipped with a passive circuit.

[[Fender Stratocaster]]-type guitars generally have three single-coil pickups, while most [[Gibson Les Paul]] types have humbucker pickups.

Piezoelectric, or piezo, pickups represent another class of pickup. These employ [[piezoelectricity]] to generate the musical signal and are popular in hybrid electro-acoustic guitars. A crystal is located under each string, usually in the saddle. When the string vibrates, the shape of the crystal is distorted, and the stresses associated with this change produce tiny voltages across the crystal that can be amplified and manipulated. Piezo pickups usually require a powered pre-amplifier to lift their output to match that of electromagnetic pickups. Power is typically delivered by an on-board battery.

Most pickup-equipped guitars feature onboard controls, such as volume or tone, or pickup selection. At their simplest, these consist of passive components, such as [[potentiometer]]s and [[capacitor]]s, but may also include specialized [[integrated circuit]]s or other active components requiring [[battery (electricity)|batteries]] for power, for preamplification and signal processing, or even for [[electronic tuner|electronic tuning]]. In many cases, the electronics have some sort of shielding to prevent pickup of external interference and noise.

Guitars may be shipped or retrofitted with a hexaphonic pickup, which produces a separate output for each string, usually from a discrete piezoelectric or magnetic pickup. This arrangement lets on-board or external electronics process the strings individually for modeling or [[MIDI|Musical Instrument Digital Interface]] (MIDI) conversion. [[Roland Corporation|Roland]] makes "GK" hexaphonic pickups for guitar and bass, and a line of guitar modeling and synthesis products.<ref>{{Cite web|title=The GK Pickup|url=http://www.roland.com/V-Guitar/about.html|access-date=2020-07-20|website=Roland V-Guitar|language=en}}</ref> [[Line 6 (company)|Line 6's]] hexaphonic-equipped [[Variax]] guitars use on-board electronics to model the sound after various vintage instruments, and vary pitch on individual strings.

MIDI converters use a hexaphonic guitar signal to determine pitch, duration, attack, and decay characteristics. The MIDI sends the note information to an internal or external sound bank device. The resulting sound closely mimics numerous instruments. The MIDI setup can also let the guitar be used as a game controller (i.e., Rock Band Squier) or as an instructional tool, as with the [[Fretlight]] Guitar.