Question about Sonos Arc

If the projector has neither ARC nor eARC and does not offer an optical interface for sound (also known as Toslink), it will be difficult. Bluetooth is not supported by the Sonos Arc or the Sonos One (SL). Only the Sonos Era devices can do this.

Sonos speakers are typically used in a WLAN network (e.g. also for control). The Sonos One (SL) is connected to the Sonos Arc during setup via a WLAN that the Sonos speakers themselves establish with each other.

In my opinion, which may be wrong, it is not possible to connect the Sonos Arc to the projector. However, it may be possible to connect the player to the Sonos Arc. If the player (e.g. BluRay player) has an optical output (Toslink), this can be connected using an adapter. The adapter is already included with the Sonos Arc.