A chord whose notes are played one at a time in rapid sequence rather than simultaneously, commonly produced by a synthesizer arpeggiator cycling through chord tones automatically.
An arpeggio is a chord whose notes are triggered one at a time in succession rather than all at once, producing a melodic pattern from harmonic material. In electronic music, a synthesizer arpeggiator automates this process by cycling through the held notes at a set rate, typically sixteenth notes or eighth notes, locked to the track's tempo.
Why it matters
Arpeggiated synthesizers are rhythmically dense and harmonically specific, so they can expose key conflicts during a blend far more clearly than a pad or a sustained chord. A DJ needs to know the key of an incoming arp-heavy track before blending, because the arp will cycle its pitches continuously and any mismatch with the outgoing track's root will be immediately audible.
In practice
When the arp enters during a blend, monitor it in the headphones against the outgoing track before opening the channel fader. If there is a key conflict, filter the arp down or bring it in low until the outgoing track's harmonic content is cleared.
