Spotify Technology SA is looking to charge as much as $5.99 a month on top of existing subscriptions for a new super-fan streaming service that will include higher-quality audio, remixing tools and access to concert tickets, people familiar with the matter said.The company hopes to roll out the Music Pro tier later this year, said the people, who asked not to be identified because the plans are confidential. The pricing and timeline aren’t set because Spotify is still working through the details...