You will probably be able to drive them with an unblanced cable that shorts pins #1&3 of the XLR together, and this goes to the ground tab of the RCA plug. Pin #2 of the XLR goes to the center "hot" pin of the RCA. It is actually cleaner from a sound quality standpoint if you can use unbalanced connections. The only use for balanced connections is if you run very long cables, like over 50 feet or so in a hostile environment around AC lines and motors.