Yes, you can connect a Bluetooth turntable to the Roam and play the turntable audio to the rest of your Sonos speakers.

Are you sure, @GuitarSuperstar ? I thought it could connect to wifi or Bluetooth but not both together. 

From the Roam announcement post:

"Seamless connectivity also unlocks Bluetooth streaming for your entire system, with the Sonos app allowing you to group any of your Sonos speakers to Roam when streaming with Bluetooth".

I stand corrected. @GuitarSuperstar is correct; thanks  @John B 

It’s one of the interesting features provided by the different ‘radio’ in the Roam versus the Move, the ability to have both energized at the same time. I’d assume it’s a hardware change, if it was only software, they’d have enabled it on the Move at the same time.

does this work with Ikea Symfonisk speakers as well?

Yes.