There are so many songs being released these days that it’s impossible for music web sites to keep up with all of the data they need to synthesize about the music. The big media sites can do it, but The Echo Nest helps level the playing field for the rest of the music sites.

It does so with something it calls “the musical brain.” It’s a “musical intelligence platform” that synthesizes a ton of music information. For a given song, it will find out what bloggers have said about it and analyze the song itself in terms of tempo, harmonic structure and other characteristics. It then creates a big pile of data that it can feed to music web sites.

Sites such as Imeem can use the data feed to create things such as a music recommendation engine. You type in Herbie Hancock at the site and it finds artists who have similar styles, based on the analysis of the characteristics of Herbie’s songs. Such engines can be created with very little work.

The company said today that it has raised its first round of venture financing. The deal (of undisclosed size) was led by Commonwealth Capital Ventures. Angels also participated. The company has also released development tools for web sites to use to incorporate the Echo Nest platform into their sites.

Competitors include All Music Guide and Muze.