Arpeggios and retro tricks

With only a few voices you often can not play a full chord — so chiptune fakes it with an arpeggio: cycling through a chord’s notes very fast (e.g. root–third–fifth every frame). Played quickly it sounds like a shimmering chord from a single channel. This "arp" sound is one of the most iconic chiptune textures.

• Arpeggio — rapidly cycle chord notes to imply a chord on one voice
• Vibrato — a slight, fast pitch wobble adds expression
• Echo / delay — repeat a note quieter a beat later to fake reverb depth
• Duty-cycle changes — switching the pulse width changes the tone color