Some 400 different elements of a song are noted, providing the backbone of what Westergren calls the Music Genome Project, which fuels Pandora.
It can tell you that if you like Steely Dan, you’ll also dig Pink Floyd. It can define what The Police’s Every Breath You Take is really all about.
Consider singer Sting’s “breathy alto,” Westergren says, or the synthesizer and drum sounds provided by Stewart Copeland. “We’ve taken each one of those things and measured them and captured the musical DNA of the song,” he says. “So when you say, ‘I like Every Breath You Take,’ we break that down into musicological information and find the songs that share those characteristics.”
To get the most out of Pandora, listeners are urged to use the “thumbs up” and “thumbs down” features when a song plays to tell the software what they like and don’t like.
“It’s like creating a bonsai tree,” says Westergren, “where you clip some branches and let others grow and shape the station over time.”
Even with the fine-tuning, Pandora’s library is just 710,000 songs. Competitors Slacker, Rhapsody and MOG have 4 million to 6 million songs. If you listen to the same station for hours upon hours, you will hear a lot of repeats
