Earlier quoted context omitted.
I don't even know what an Arpeggiator is, sounds cool though.
If you play a chord into an arpeggiator, it... well, it arpeggiates it. In other words, it plays each note of the chord individually in a particular rhythm (e.g. 16th notes) in a particular pattern (e.g. up/down, up, random). Very, very common in electronic music.
Does it get scaled in specific patterns or is random ok?