Spotify playing on Yamaha CX-A5100 without Sign-in Account

[DFWNguyen]

I am currently not a Premium user (free access) and here is my dilemma/question:

- I've been playing music from my iPad/iPhone through the Yamaha AV Controller via AirPlay and/or Bluetooth using my Spotify sign in - no problem, however,

- I've recently discovered that the Yamaha AV Controller also has the option to choose Spotify in the "Input" without my iPad/iPhone or sign-in.  The music streams directly to my Yamaha CX-A5100 much clearer (higher resolution) than the free stream coming from my iPad/iPhone but without me being able to control what's being played other than skipping . . .

    *  Is this a promotional stream, which I have no control, to atract users for what the sound quality can be with Premium?

    *  If this is available for free-access users, how can I log in to be able to control what's being played (directly from the Yamaha processor with or without  my iPad/iPhone like Pandora)?

    *  If this is for Premium users only (which I would sign up), can Spotify be played with the sign-in directly and the play lists controlled from the Yamaha AV controller app (without my iPad/iPhone)?

Thanks for your help.