DESC: The ProMonitor® 60 The ProMonitors are a masterpiece of engineering and design virtuosity. They are beautifully sculptured, ultra-compact, magnetically shielded main or rear channel full-range systems. The cabinets are molded of a Definitive developed high-density, mineral-filled, non-resonant polymer material called PolyStone™. Housed in 3-1/2" bass/midrange driver and a 1" pure aluminum dome tweeter (the same basic high-end drivers used in our top-of-the-line bipolar SuperTowers), perfectly blended together with a complex Linkwitz-Riley crossover network. The rear and sides of the enclosures are actually one continuous compound curve which has very specific performance benefits in addition to its obvious styling attributes.