Fans of Imogen Heap can buy a lot with just $1 this summer. For just a buck, you can get a new, unique track from the Grammy-winning British musician created in your city — with the happy knowledge that your money is going towards a worthwhile charity near you.

That's because Imogen Heap decided to pursue a unique fundraising effort with her Ellipse World Tour. At her concerts, Imogen Heap improvises a song using parameters selected by the audience — then makes those tracks available online for $1. All proceeds go to local charities, many of them with a green goal. The track created in Detroit, for example, benefits Urban Farming — a local nonprofit that seeks to grow food in unused land, space, rooftops and walls.

I, of course was curious about what Imogen Heap did at her June 12 concert at the Greek Theatre in Los Angeles. Today I finally listened to the track online and heard Imogen Heap put her improvisational skills towards helping a local environmental nonprofit called TreePeople. Fans decided — by the loudness of their cheers — the key, meter, and tempo for Imogen Heap’s L.A. piece. Then the artist put the votes to sound, creating an ethereal and moody track in E-flat minor, in 4/4 at 152.55 bpm.

Listen to the tracks free online — then pay a buck to download the track of your choice. The dollar gets you both the edited track and the longer unedited version that lets you hear how Imogen Heap and her audience went about setting the track’s musical parameters. For music nerds, it is really kind of exciting to hear people get excited enough to scream in support of their favorite musical meter! 

Each track is only available for two months after the release date, so don't delay too long before donating and downloading. Imogen Heap's goal is to raise $54,353 for charity; so far $19,103 has been raised.

Imogen Heap improvises for the environment
The Grammy-winning artist lets you buy a track she created during a performance in your city for $1 -- all of which goes to a local charity.