> What's a paid service that facilitates access to unknown artists?
Other people have been mentioning Bandcamp. Seems like signing up as an artist is free, and they market themselves as a way to discover and support new music. Am I missing something, or isn't that the kind of service you're talking about?
Not the denigrate Bandcamp but I think the thing Soundcloud has that a Bandcamp-like-system doesn't have is the ability to create a "music scene" - sure, Bandcamp is helpful for artists, allowing them to sell stuff to people who are already familiar with them. The key of soundcloud afaik is being able to share a simple link to anything you've done.
The creation of new music has always involved exposing penniless people to it and no current music subscription service comes remotely close to that.
One alternative might be integrating peer-to-peer with a music discovery system.
Edit: craigslist and meetup are closest thing to "mass culture websites" and they each get a small minority of users to pay for their operations.