Thanks for reaching out and welcome to the Bose Community Forums.
Bose SimpleSync is a new technology that allows you to pair a member of the Bose Home Speaker family with select Bose portable Bluetooth speakers or Bose Noise Cancelling Headphones 700. It’s really simple to use, you can find all of the details here.
To further answer your question, you would be unable to connect any third-party Bluetooth headphones to the Soundbar 500.
Let me know if you have any other questions.
Vicky W - Community Support
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