As others have said, if it’s a niche hobby lemmy is probably too small to see a lot of activity. Depending on what you’re envisaging, maybe posting on bigger general communities like c/music is more likely to get responses and interest.

But if you are interested in starting a community, go for it! If it’s small, there’s not really going to be any issues with moderation (or that’s been my experience at least). And if anything does come up there are places here to ask for advice and guidance. But the main issue is that you’ll probably need to promote the community and do a lot of posting without much response until it grows. If that sounds hard, then just post to bigger, appropriate communities and get people interested, and maybe later a specific community had arise once it’s needed.