Thank you for your post and welcome to the Bose Community.
The Solo 5 TV Sound System is not compatible with any additional wireless speakers. I apologize if this may be disappointing for you.
If you are looking for a system that does allow the addition of wireless speakers, I would recommend checking out the Smart Home Soundbars. The Soundbar 500 or Soundbar 700 are both compatible with the addition of a bass module and wireless speakers.
If you require any further information, please do not hesitate to reach back to me.
Charlotte G - Community Support
I also have a Bose Solo 5 and I combined it with two ST III 20's and one ST III 10. If you buy a Soundtouch wireless link adapter and connect it to the imput of the Solo 5 you can play roomfilling multiroom.
Thanks for helping out here.
That's a great idea and I am so happy that it works for you.
If any other users have any ideas we would love to hear from you.