I posted and replied to clubhouse related stuff in sub reddits two days ago, rewarding me with my first 10 email sign-ups.
I'm not mistaking this them for becoming actual users, but the idea alone (my landing page is very basic) seems to have interest by people that want to / are actively use Clubhouse.
Trying to grow this besides working on the last code for my version 1 will be interesting the next week.