We had a good solution for that problem - we built a room-in-room construction in our rehersalroom. Its basically a small box, where the drumset plus the drummer and a frew microphones are placed in. that box has to be isolated very good ,so that you hardly hear something on the outside. then you just put your drummer on the PA (via the microhones - just like in a studio). and viola - a drummer that can be turned off when necessary *LOL*