Editing Tremolo (section)

== Types of tremolo ==

=== Rapid reiteration or oscillation ===
The rapid reiteration of a single [[Musical note|note]] is a characteristic effect of [[String instrument#Bowing|bowed string instruments]], obtained by rapidly moving the bow back and forth. However, the technique may be performed on any instrument on which it is practicable. (Indeed, a slow measured tremolo is simply a shorthand notation for an ordinary repetition of notes; thus, tremolo notation may appear in written music for any instrument.)

The notation for this effect consists of one or more strokes drawn through the stem of a note (or, if the note lacks a stem, through the position that a hypothetical stem would occupy); the strokes correspond to the beams that would connect the individual repeated notes if they were to be written out, thereby representing the rate of repetition (the speed of the tremolo).

[[File:Page 15 Ex.4 (A Dictionary of Music and Musicians-Volume 1).png|thumb|upright=2|Tremolo examples (repeated notes)]]

Some special cases are worth noting:
* On plucked strings such as on a [[harp]], the word ''[[wikt:bisbigliando|bisbigliando]]'' ({{IPA|it|bizbiʎˈʎando}}) or "whispering" is used. [[Tremolo picking]], on traditionally plucked string instruments including guitar and mandolin, is the rapid articulation of single notes or a group of notes with a [[plectrum]] (pick) or with fingers. Tremolo playing sustains notes that would otherwise rapidly decay (fade to silence).<ref name="Examples of Tremolo on Acoustic Guitar">{{cite web|url= https://www.youtube.com/watch?v=Fd3NAh7klSY |archive-url=https://ghostarchive.org/varchive/youtube/20211211/Fd3NAh7klSY| archive-date=2021-12-11 |url-status=live| title=Examples of Tremolo on Acoustic Guitar |work=[[Kapil Srivastava]]| via= YouTube| access-date= August 12, 2020}}{{cbignore}}</ref><ref>{{cite web|url=https://www.mandolincafe.com/glossary/glossary_32.shtml |title= Mandolin Glossary: Tremolo |website=Mandolin Cafe| access-date=March 28, 2022}}</ref>
* The technique of [[flutter-tonguing]] on [[wind instruments]] is analogous to an unmeasured tremolo on strings, and notated similarly.
* The [[drum roll|roll]] on [[percussion instruments]] is one of the most familiar examples. On unpitched instruments, as well as [[timpani]], it may be notated as either a tremolo or a [[trill (music)|trill]] — a fact suggestive of the close relationship between tremolos and trills (see below).

A rapid alternation between two different pitches is another type of tremolo. On bowed string instruments, this is referred to as a ''fingered tremolo'' to distinguish it from the ''bowed tremolo'' discussed above; but once again it may be performed on any instrument. It is notated by writing the pitches to be alternated as a [[melodic interval]], with both notes receiving the rhythmic value of the total duration of the tremolo (e.g. two half-notes for a tremolo lasting a [[half-note]]), and then either connecting them with beams, or else interpolating strokes, with the number of beams or strokes corresponding to the speed of the tremolo (e.g. a tremolo in [[thirty-second notes]] lasting a half-note would be written either as two open noteheads connected by three beams, or as two half-notes with three strokes interpolated).

:[[File:Tremolo notation two notes.svg|thumb|upright=2|Tremolo examples (alternating notes)]]

This type of tremolo includes the [[trill (music)|trill]] as a special case: a trill is simply an unmeasured tremolo between two notes separated by the interval of a [[major second|major]] or [[minor second]] (whole- or half step). Thus, a tremolo in this sense is a generalization of a trill to any interval, and to include measured durations.

=== Amplitude variation ===
[[File:Fuse Electronics Tremolo MK-III Quick Demo.ogg|thumb|Video of a tremolo [[Effects unit|effect pedal]], producing a cycling variation of volume, played with an [[electric guitar]]]]A separate type of tremolo is a variation in [[amplitude]]:
* As produced on organs by [[tremulant]]s
* Using electronic effects in guitar amplifiers and effects pedals which rapidly turn the volume of a signal up and down, creating a "shuddering" effect
* An imitation of the same by strings in which pulsations are taken in the same bow direction
* A [[vocal technique]] involving a wide or slow [[vibrato]], not to be confused with the [[Trill (music)#Trillo|trillo]] or "Monteverdi trill"
Tremolo is sometimes used interchangeably with vibrato. However, a tremolo is a variation of volume (or amplitude); as contrasted with [[vibrato]], which is a variation of pitch (or frequency).
[[File:Fender Pro Amp brownface (1960s, pre-CBS) front panel - mid.jpg|thumb|"Vibrato" channel on a 1960s [[Fender (company)|Fender]] Pro Amp Brownface [[Guitar amplifier|electric guitar amp]]. The effect produced is actually a tremolo.]]
Some [[electric guitar]]s (in particular the [[Fender Stratocaster]]) use a lever branded a "tremolo arm"<ref name=":0">{{Cite book |last=Hunter |first=Dave |url=https://books.google.com/books?id=hVP0AwAAQBAJ&pg=PA221 |title=The Fender Stratocaster: The Life and Times of the World's Greatest Guitar and Its Players |date=2013-11-16 |publisher=Quarto Publishing Group USA |isbn=978-1-61058-878-2 |pages=221 |language=en}}</ref> or "[[whammy bar]]" that allows a performer to lower or (usually, to some extent) raise the pitch of a note or chord, an effect properly termed [[vibrato]] or "pitch bend". This non-standard misuse of the term "tremolo" refers to pitch rather than amplitude.<ref name=":0" /> However, the term "trem" or "tremolo" is still misused to refer to a [[Bridge (instrument)|bridge system]] built for a whammy bar, or the bar itself. True tremolo for an electric guitar, [[electronic organ]], or any electronic signal would normally be produced by a simple [[amplitude modulation]] [[electronic circuit]], or in terms of [[analog synthesis]], a [[Variable-gain_amplifier|VCA]] under control of an [[Low-frequency_oscillator|LFO]]. Electronic tremolo effects were available on many early [[guitar amplifier]]s. [[Fender (company)|Fender]] labeled them Vibrato, adding to the confusion between the two terms.<ref>{{Cite book |last1=Teagle |first1= John |url=https://books.google.com/books?id=kO8y6J6Is_4C&pg=PA225 |title=Fender Amps: The First Fifty Years |last2=Sprung |first2= John |date=1995 |publisher=Hal Leonard Corporation |isbn=978-0-7935-3733-4 |pages=225 |language=en}}</ref> Tremolo effects pedals are also widely used to achieve this effect.

Most settings on a tremolo effects pedal include depth of the tremolo (sometimes called intensity) and speed of the tremolo. Some models allow to choose the shape of the waveform ([[sine wave]], [[triangle wave]], [[Square wave (waveform)|square wave]]).<ref>{{Cite book |last=Hunter |first=Dave |url=https://books.google.com/books?id=sM5azHTPaQ4C&pg=PT311 |title=The Rough Guide to Guitar |date=2011-02-01 |publisher=Rough Guides UK |isbn=978-1-4053-8873-3 |pages=311 |language=en}}</ref>