Some of the differences between the two versions of Airplay are ‘outlined’ below:

• Airplay doesn't offer multi-room audio; AirPlay 2 does
• AirPlay lets you stream from any Apple device to your speakers or TV
• AirPlay 2 lets you play from speakers over Wi-Fi, and it'll stay in sync
• AirPlay 2 lets play different songs in different rooms with multiple HomePods

And ‘Yes’ if you add a Sonos One speaker to your existing setup, you can group the speakers and Airplay to the group - the Sonos One will handle the audio stream to the other players.

Important to note that adding a Sonos One doesn’t make your PLAY:1s available as an AirPlay 2 target. As Ken says, you’ll need to target (send) the AirPlay 2 signal to the Sonos One, and then group that speaker with any of the PLAY:1s to get that signal to them. 

Sonos does not support AirPlay (1) signals, only AirPlay 2. 

If you have the technical know-how, it’s easy to create an AirPlay (v1) bridge for your Play:1 speakers using AirConnect:

https://github.com/philippe44/AirConnect

This allows direct AirPlay playback on your Play:1s. It’s very reliable, with audio quality up to and including lossless. One running instance of AirConnect can handle multiple AirPlay streams (different Apple devices to different Sonos speakers).

If you want to play audio in sync with other Sonos devices, just use Sonos grouping.

And if I order a Roam ? Would it be a solution ? should I be able to connect the roam by airplay and  sync with my 2 play:1 ?

Thank you for your answers.

Yes, the Roam is another option you can use… in fact it also will provide you with Bluetooth audio input, aswell as Airplay, and when it’s also linked to your WiFi network, you can stream either Airplay or Bluetooth audio to it and then group the Roam with your existing speakers to play that audio source on them too. So it’s perhaps a better option if you need to play audio via Bluetooth. 

AirPlay 2, not AirPlay. Just to be pedantic. 

I was just trying to save on ink.  ha ha.

LOL, I get it. The problem is, every now and again, it seems like people point to data like that and say “but it said….”

There is a lot of FUD around AirPlay 2 and the way that Sonos interfaces with it. I’ve seen many posts in which people assume that when they add a Sonos One, the PLAY:1s suddenly become AirPlay 2 targets. They don’t really realize that it’s the hardware that makes a difference, there’s nothing in the software that magically changes when you add a Sonos One. But there you go :)

Edit: I will admit to being OCD about certain things. Not everything, mind you. 

I’ll just add that AirPlay 2 handles audio/video synchronisation.

For example, if you’re playing a video on your iPad and send the audio to an AirPlay 2 device, the video and audio will be in sync. This is not the case for AirPlay v1, and is the most important enhancement for my use cases.

Ah thanks @pwt.