8" 50W coaxial driver with 20 oz. LF magnet coupled with 1.4" copper voice coil drive a polypropylene cone with half-roll rubber surround for long cone travel and good edge damping. Post-mounted tweeter is a 1" balanced-drive dome protected by Ferrofluid and a first-order high-pass filter. Speaker frame is stamped 20-ga. steel with black enamel finish and zinc plated backplate. Mounted and wired 70V transformer (No. TLM-1670) has primary taps at 4, 8, 16W