I can pair soundbar 500 with bass 500 by remote control. I tried with soundbar 700 and it good work. I don't know soundbar 500 pair bass module with remote no need Bose Music app.
Thanks for posting.
You will need the app to pair the Bass Module to the 700.
Hector B - Community Support
You will need the Bose Music App, then go to Settings > Accessory Speakers and you can add the Bass Module there.