A friend of mine saw a front projector and was stunned that something like that existed. He is going to go buy one. I told him that he needed to buy a decent sound system to go along with it otherwise he would really be missing out. He was in a rock band for many years and still has a lot of equipment. He asked if he could use his subwoofer from his band days. It is a sealed single 18 inch driver that has an external amplifier. He has many amps. I am not sure what he wants to use, but wattage is not an issue. Is this OK?