Well, the beauty of the Sonos platform is that you can have multiple music sources (local libraries on a PC or NAS, subscription/streaming services) and controllers (PC/Mac desktop, phone, tablet) as part of your set-up. And you can start with one Sonos unit and one controller and then expand.



Any modern iOS / Android device should run the controller app, a bigger screen would work better (although an iPod touch or old phone will still work fine).



You choice might depend on budget, what your music sources are, and expected file sizes / formats if you're looking to have a local library of purchased music from CDs/downloads.

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