A:Answer Hello!
Thank you for your interest in our speakers.
If you were to connect the wired outdoor receivers to a Sony receiver, this will not be able to then connect and play in sync with the SoundTouch 30 III you have mentioned here.
If you were using our SoundTouch SA-5 Amplifer, then you would be able to connect the outdoor speakers to this amplifier, and then sync these up to play Wi-Fi or Bluetooth sources at the same time as the SoundTouch 30 III.
We hope this helps clear this up for you!