What is an arpeggio?


According to the musical theory, an arpeggio is a type of a broken chord in which the notes that compose the chord are played or sung in rising or descending order. An arpeggio can also span more than one octave. Even though the notes of an arpeggio are not played or sung all together at the same time, listeners hear the sequence of notes as forming a chord.


Arp instruments in synths


Most of today synthesizers posses the arpeggiator feature. In essence, an arpeggiator is a very basic real-time sequencer. It takes a chord as an input and turns it into an arpeggio. Ever since they originated in the early days of hardware synthesizers, their simplicity and immediacy captured the attention of musicians ever since.

Arpeggiator history


The history of arpeggiator began with dedicated hardware synthesizers of late 1960`s and 1970`s. Later on, they became an inevitable part of some of the famous analog synthesizers like Roland Jupiter 8, Oberheim OB-Xa, Roland SH-101, Roland Juno-6, Sequential Circuits Six-Trak, and Korg Polysix just to mention a few.

The period of late 1980’s and the beginning of the 1990`s brought an absence of arpeggiator feature among top-selling synthesizers. Yamaha DX-7, Casio CZ-101, Roland D-50, and Korg M1 didn’t have this feature. However, the great comeback in the interest of analog synthesizers happened in the 1990`s. This is because some dance music hits incorporated arpeggiator sequences, brought interest for arpeggiators once again. Consequently, most popular synthesizers manufactured since the mid-1990s include such a device.


Chord progressions


Music is typically based around progressions of chords. However, this may not be so obvious. This means that the players may not play the notes of the chords together simultaneously. As an example, you can think of a guitarist playing finger-style, and using intricate plucks to create a far more complex pattern. Often, this is still based around simple chord shapes.

An arpeggiator takes advantage of this fact and provides synth players with an easy way of playing complex synth parts via simple chords. Switching on an arpeggiator tells the synth to ‘listen’ to the notes that synth players play. Then, it creates a pattern (an arpeggio, typically) using these notes, played at a set master tempo. The player only needs to hold the notes. Or, if the arpeggiator has a ‘latch’ function activated, just hit the chord once, and the pattern will continue to play until another note, or chord is hit.


Modern Arpeggiators


At its most simple state, an arpeggiator will simply cycle through the notes played, either up or down in pitch, playing each note to a specified note length. Modern arpeggiators, however, have far more options. Typically, even a modestly equipped arpeggiator will have the option to switch between ‘up’, ‘down’, and ‘up and down’ modes, with a random mode usually thrown in for good measure. These, with the ability to change tempo and note-length, represent a surprisingly creative set of tools in their own right.

More sophisticated designs will offer the user to specify more complex pre-programmed patterns, or even program their own. Some arpeggiators allow for polyphonic patterns. This means that the chords are tempo-synchronized. Often, synth players can set octave ranges. This means that notes held will leap up, or down to higher or lower octaves according to the notes held and specified a pattern. Workstation style synths often have immensely complex arpeggiators. They allow the user to program multiple layers of sounds with differing patterns. such. As a consequence, users can create very complex, evolving, layered sounds.


Additional resources & source texts

What Is An Arpeggiator?