Amazon wants to sell a cheaper music subscription service that will only work on its Echo player

Amazon wants to launch a music subscription service that would work the same way services from Apple, Spotify and many others work: $10 a month, for all the music you can stream, anywhere you want to stream it.But Amazon is also working on a second service that would differ in two significant ways from industry rivals: It would cost half the price, and it would only work on Amazon’s Echo hardware.Industry sources say Amazon would like to launch both services in September, but has yet to fi