Your safest bet is to politely go over to their door, knock, introduce yourself and explain your situation. Don't ask permission-- just tell them what you're doing with your drums. Give them your phone number and ask them to call if the noise becomes unreasonable or disruptive.
If it's just a distant banging, people get pissed and call the police. If they have a face to put with the noise, and that face is a nice person, they'll be a hundred times more tolerant.