It looks like it sets up a wireless stream, which you (I’m guessing) add as a Service and select as a music source. If so, it should indeed work with your Play:1 and Play:3, as their website says. 
 

Correction:

The tt is set up as a device on your wifi network, and their app auto plays to a selected default speaker, whatever speaker you chose in your system. As it auto plays, when you start playing vinyl the sound comes from your Sonos device. Then in the Sonos app you can group other speakers etc in the normal way. Not clear though if your selected Autoplay speaker always has to be in the group or whether you can have that speaker playing a different source whilst the tt is playing to other Sonos devices. 
 

So yes: it will work with your older model speakers.