In music, an arpeggio (plural arpeggi or arpeggios, or known as a broken chord) is Italian for broken chord where the notes are played or sung in sequence, one after the other, rather than ringing out simultaneously. This word comes from the Italian word "arpeggiare" , which means "to play on a harp". Formed from scales, the arpeggio is based on the relative scale playing the "key" notes or those affected by the key signature.
An arpeggio is a group of notes which are played one after the other, either going up or going down. Executing an arpeggio requires the player to play the sounds of a chord individually to differentiate the notes. The notes all belong to one chord. The chord may, for example, be a simple chord with the 1st, 3rd, and 5th notes of the scale in it (this is called a "tonic chord"). An arpeggio in the key of C major going up two octaves would be the notes (C, E, G, C, E, G, C).
An arpeggio is a type of broken chord. Other types of broken chords play chord notes out of sequence or more than one note but less than the full chord simultaneously. Arpeggios can rise or fall for more than one octave.
Students of musical instruments learn how to play scales and arpeggios. They are often a requirement for music examinations.
An "arpeggiated chord" means a chord which is "spread", i.e., the notes are not played exactly at the same time, but are spread out. Arpeggiated chords are often used in harp and piano music. An arpeggiated chord may be written with a squiggly vertical line in front of the chord. It is spread from the lowest to the highest note. Occasionally, composers such as Béla Bartók have asked for them to be played from top to bottom. This is shown by adding an arrow pointing down.
Any instrument may employ arpeggiation, but the following instruments use arpeggios most often:
In Western classical music, a chord that is played first with the lowest note and then with successive higher notes joining in is called arpeggiato. Sometimes this effect is reversed, with the highest note coming first. In some modern popular music arpeggiato is called a "rolled chord".
In early video game music, arpeggios were often the only way to play a chord since sound hardware usually had a very limited number of oscillators, or voices. Instead of tying them all up to play one chord, one channel could be used to play an arpeggio, leaving the rest for drums, bass, or sound effects. Examples include the music of games and demos on Commodore 64's SID chip which only had three oscillators, see also Chiptune.