
These include Righteous Babe, Nettwerk, Madacy, Nitro Records and labels represented by Digital Music Group, the Digital Rights Agency and the Independent Recording Industry Services.
MusicNet will make the tracks available for distribution in the MP3 format at a higher sound quality.
The move follows EMI's landmark decision in May 2007 to drop DRM in a deal with Apple.
"Interoperability has been a sore spot for the digital music industry since its inception and continues to grow as devices become more widely used," said Alan McGlade, president and chief executive at MediaNet Digital.
"The digital music industry has been built on the appeal of MP3, an open, standardised format which is usable on every digital music player, desktop computer, electronic device and gaming system.
"The music labels making these first million tracks available for unencrypted download will help fuel alternative mechanisms of accessing digital music, giving consumers a choice in how they interact with their music."
Lauren Berkowitz, senior vice president at EMI Music North America, added: " MusicNet is an important distribution partner for us and we are pleased that it will make EMI's digital catalogue in DRM-free, higher quality offering available to the great brands they power.
"It is an important step forward that will put more music in reach of fans in formats that will allow them to enjoy what they purchase on a range of devices."