Monitor Audio Develops New Platinum II Speaker Range Monitor Audio's Platinum II series offers an audiophile performance in design and materials specification.RS Staff ⋅ Dec 2, 2015 Inspired by new analysis by the Monitor Audio engineering team, the company’s Platinum II series offers an audiophile performance in design and materials specification. Monitor Audio’s engineers focused on the operation of electrical, mechanical, magnetic, and acoustic systems, deploying a new MPD (Micro Pleated Diaphragm) high-frequency transducer, supported by RDT II bass and mid drivers, improved crossover design, and bespoke speaker terminal designs. The new seven-model lineup premieres the flagship PL500 II tower; two additional floor-standing models, the PL300 II and PL200 II; the PL100 II stand-mount monitor; PLC350 II and PLC150 II matching center-channel speakers; and a 1400-watt, twin 15-inch subwoofer, the PLW215 II. The MPD high-frequency transducer uses a thin, low-mass, pleated diaphragm and a tweeter that operates with uniform output to over 100 kHz. RDT II is a composite ‘sandwich’ structure made from ultra-thin low-mass skins, bonded to a honeycomb Nomex core material. RDT II employs C-CAM for the front skin, while the rear skin is made from a woven carbon fiber material. All Platinum II drivers were designed using “underhung” voice coils, which ensure that even at extreme excursions , the coil remains within the gap, converting all the electrical energy into movement and resulting in greater efficiency and driver linearity. The new edge-wound coil design packs more copper into the shortest space to maximize driver excursion. The company redeveloped the crossovers using air core inductors in the midrange and tweeter sections and laminated steel cores for bass sections. Custom-made, audiophile-grade metallized polypropylene capacitors operate within a 1 percent tolerance for the best possible sound quality. Platinum II speakers are internally wired using Monitor Audio’s silver-plated OFC copper cable. Platinum II’s bespoke speaker terminal design is milled from solid copper with Rhodium-plated conductor parts. Rhodium is favored for its electrical conductivity and resistance to oxidization. Terminals are designed to accept a spade, 4 mm banana plug, or bare wire up to a diameter of 4 mm.