
This USB-C to 3.5 mm adapter lets you connect a compatible external audio source — such as a turntable, laptop, or CD player — to Sonos Era 100 or Era 300.
A: You only need one and that speaker will communicate with your other speakers.
Q: one end adapts to a era 300 speaker and what type of cable adapts to tv fiber optic?
A: The 300 does not have an optical connection. To the best of my knowledge the only Sonos items with optical connections are the sound bars. This cable is strictly a line in connection. We use it to connect our turntable to our speaker.