Model PD75T is a fully environment-resistant 75 Watt driver for indoor or outdoor applications and is recommended for use in expansive and/or high ambient sound-level areas. This model features a sound chamber, phasing plug, magnetic-structure components machined to optimum tolerances, 2" voice coil and offers a plane wave frequency response of 100Hz – 3.7kHz (+5dB).This unit, which is comprised of a transformer with 16 ohm bypass, will meet a variety of applications. The PD75T provides screw-type terminals for matching direct to the 16 ohm voice coil impedance and a built-in varnish impregnated, multi-tap 70.7 volt line-matching transformer. Corrosion-resistant terminal connections are protected by a transparent, impact-resistant plastic cover. The PD75T is terminated in a standard 1 3/8"–18 thread male couplings for use with screw-on horns, or with Atlas Sound Model YDA-TH adapters for bolt-on large format horns. Diaphragms are replaceable with appropriate equipment. A replacement diaphragm, model PD75TDIA, is available. Internal components are enclosed within a protective die-cast and polycarbonate injection molded housing and finished in gray baked epoxy.