it's similar to being a vocalist, except instead of it coming out of your throat, you're controlling it just in the air and you don't really have a point of reference you're always relying on your ears and adjusting constantly.

Out in the hall with their crocodile tears Now that you're out of it, now that you're leaving, Now that they've sealed your arse and your ears, What I've been meaning to tell you for years, And years, and years, and years, old friend ...