I see this is an old thread, but I just had this problem this weekend. Friday night people were saying that they could not hear my vocals. My "boss", the bass player who is the sound guy as well, liked the SM58 on my voice because it sounded warmer. But it picks up the snare hits so much that he would not put my fader up enough to get my vocals out there. So I went back to using my hypercardioid Audix OM2, and that solved the problem. It's a "drier" mike though, it lacks the warmth of the 58, but with a little eq it can be made to sound better. Drums are a huge "noise floor" issue when trying to sing over them, a hypercardioid is the answer to snare bleed.