Blue makes some pretty good microphones. So when they teamed up with Interscope Records and Beats by Dre, they created a monster mic. The mic is so good, purportedly, that it is featured on American Idol. The young idolers started using the mic during last night’s performance.
The mic is said to have been designed by Dr. Dre — I’m assuming he has a PHD in EE at this point — and includes wireless technology from Line 6 and a unique detailed and clear mic head design from Blue. The mic is more of a collaba-mic then anything else. 
The mic is specially built for the reality show, at least for now, but there are wired versions for sale now.