With the SoundTouch wireless adapter, you can use the SoundTouch app to group multiple SoundTouch systems.
Your system works with the accessory SoundTouch wireless adapter. This brings SoundTouch functionality to your system, like streaming music services and mobile app control. If you have more than one Bose SoundTouch system, you can use the SoundTouch app to group them together so they play the same sound. For more info, see Grouping systems
If you are not using the app or trying to connect a different Bose product, your product will receive Bluetooth® audio but will not send Bluetooth audio to another device.
Most Bluetooth speakers and headphones, like your Bose products, are Bluetooth receivers. This means they can receive and play sound that is sent to them from a Bluetooth transmitter (i.e. a smartphone or laptop). Since your Bose products can only receive sound via Bluetooth, they cannot send sound to one another.