I personally am not involved in that many online communities, but those that I am are spectacular. I will attach my list below as well as the logic behind how to find groups for you.
Music Launch Hub | https://www.facebook.com/groups/musiclaunchhub/
The Rock/Star Collective | https://www.facebook.com/groups/rockstarcollective/
Balanced Breakfast Austin | https://www.facebook.com/groups/BBAustinTX/
Chicago Music Industry Network Group | https://www.facebook.com/groups/1779964842269048/
For me I look at groups and communities that are focused on establishing community & growth of the collective over and above pushing music or products/services. Don't worry if the location of the group is to a particular city or area, its all about the network and what they bring to you and what you can bring to them. I too am connected inside of a few communities through LinkedIn. I highly recommend to also join the app called Shapr.
Phillip Ryan Block is an artist and the CEO of Independent Ear, a successful music company specialising in recording, management, branding and booking. He recently founded Block Media Group, a Digital Ad & Creative Agency focused on branding artist and entertainment companies. Follow Ryan on Instagram.