The Vivaldi Code describes David Cope’s Experiments in Musical Intelligence software, or Emmy for short:
It all started more than 20 years ago. Cope, already an accomplished musician and programmer, sat at his piano, struggling to compose a piece. Desperate for inspiration, he imagined a computer program that could suggest a clever measure or two. So he compiled a database of his compositions and wrote some code that could detect patterns in his music and compose new riffs that follow the same rules. To his surprise, he says, the results “sounded like me.”Since then, Cope has unleashed Emmy on dozens of the great composers. Until five years ago, though, he avoided Vivaldi. Like many serious fans of classical music, he found works like The Four Seasons a bit light and repetitive. “What’s the joke about Vivaldi?” he asks the audience. “He wrote one piece a thousand times,” a faint voice answers.
But it turned out Vivaldi’s music wasn’t too simple – it was too complex. In a piece that followed a seemingly repetitive ABABAB pattern, he discovered, Vivaldi would write subtle, unpredictable variations into each recurrence of familiar material. Where the human ear focuses on obvious similarities, Emmy hears each section as a brand-new twist in the melody. Only in the past couple of years has Cope figured out how to refine his code to take the variations into account. “I fell in love with Vivaldi,” he laughs.
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“Some of it sounded like Pachelbel,” someone else suggests. “Well, that’s interesting,” says Cope, “he wasn’t in the database.” Seeing her confusion at this remark, Cope reveals a key ingredient of virtual Vivaldi’s secret recipe: works by other composers. When Emmy created music based solely on Vivaldi’s oeuvre, he explains, the results sounded authentic enough, but bland. So he threw in a few pieces by baroque contemporaries such as Tomaso Albinoni and Giuseppe Tartini. Emmy’s Vivaldi then began to stretch a bit, take risks, and, ironically, produce music that sounded more like the real Vivaldi.