The Fullragen driver has a crossover network and is connected to binding posts. So you can drive the speakers with a very "small" amplifier - a 5W triode tube amp is enough! You will have the mellow, threedimensional sound of this amplifier through the fullrange driver, supported by the powerful, fast bass fundament from the semiactive part. Plus: Adjustments like speaker position and bass setup that allow adjustment of bass reproduction according to your listening room