A new music discovery service aims to bring users who know what they want more of the sounds they like.

The new service (Pandora) can build tailored streams of music based on a user's stated music likes. It's available in the US from Pandora Media, formerly known as Savage Beast Technologies. It is based on the Music Genome Project, the company's six-year study of the 300,000 songs of over 10,000 artists undertaken by 30 musician analysts, Pandora Media said.

What's in that melody?

Analysts rated each song for 400 musical traits including melody, harmony, rhythm, orchestration and lyrics. So, if a user defines several already-rated artists, the information can be collated and analysed and returned to the user in the form if a playlist which may include songs or artists a user hasn't stumbled across before.

"This is the first music discovery service that is all about the music," said Tim Westergren, founder of Pandora. "The Music Genome Project doesn't compare your preferences or shopping habits with those of others. It doesn't care whether the artists you like (or it suggests) are already popular or just starting out. It levels the playing field by relying exclusively on the unique musical quality of each song. By painstakingly analyzing each song across 400 musical traits, we've made it easy for music lovers to discover new songs and artists."

Licensing restrictions

The first ten hours of Pandora are free. After that, subscriptions costs $3 per month or $36 per year. Subscribers can set up a maximum of 100 online stations tuned to their preferences and can tune the selection by approving or disapproving the service's selections. Users can click a "why is this song playing" button to find out the reasoning behind the company's team of analysts rating a particular song as similar to a user's original stated preference.

Due to music licensing restrictions, the Pandora service can't play songs by request, according to information on the company's site. Instead, the service uses the song title as the basis for building up a radio station, with the specific song likely to show up at some point on that station. Licensing constraints also prevent the service from offering a rewind function. Pandora has links to Amazon and iTunes so users can buy the music they hear.

The software uses Flash 6, so will run on most modern platforms and browsers.