Polkaudio XM Reference Tuner XRt12 (cir. 2005) Unit powers on, screen bright, and all controls work. Working when last used and kept in a clean environment. See photos for more details. Dedicated home XM tunerBurr-Brown digital-to-analog converterVideo output (composite) sends channel, artist, and song info to your television for easy visibilityOptical and coaxial digital outputsAnalog audio output (stereo RCA jacks)4-line blue LCD10-song memory20 channel presetsSearch by channel or categoryFeel free to message us with any more questions or concerns!

Polk Audio’s three-piece Reference Monitor speaker system, the RM-3000, consists of two small satellite speakers and a subwoofer module. Although this general configuration is currently enjoying increased popularity, Polk’s version differs from the others in many of its design details.Each of the satellite speakers is a miniature two-way system with a 3-1/2-inch “woofer” operating above 200 Hz and crossing over at approximately 4,000 Hz to a 3/4-inch dome tweeter. The tweeter is protected against burnout by an internal auto reset protection device that cuts off its signal until the power has been reduced to a safe level. The tweeter is stepped back about 1-1/4 inches from the plane of the woofer to provide proper time alignment of the outputs of the two drivers.The satellite enclosure is made of a high-density, non-resonant polymer aggregate similar to the material used for high-quality kitchen countertops. The smooth, glassy exterior is resistant to physical damage, and each of the satellites— which measure only 6-3/4 inches high, 4-1/4 inches wide, and 5 inches deep, including the molded plastic grilles—weighs a surprisingly heavy 4-1/2 pounds. The crossovers contain second-order low-pass and high-pass sections designed to complement the time alignment of the drivers. In addition to its crossover network, each satellite also contains a 200-hz high-pass filter that protects it from being damaged by high-level low-frequency signals.The subwoofer contains two 6-1/2-inch cone drivers, each driven by one stereo channel. For each channel, the appropriate satellite, the subwoofer, and the amplifier are simply wired in parallel. The subwoofer enclosure, which measures 20-1/4 inches wide, 13 inches deep, and 10 inches high, is supported 2 inches above the floor on four rubber feet. Its interior is divided into two separate sections o? different volumes, with the drivers mounted on the dividing partition. The rear surfaces of the two driver cones face the sealed volume, which provides the necessary stiffness for their proper operation. In the other section, the pressure generated by the drivers is coupled to a 10-inch passive radiator mounted on the bottom of the cabinet, facing the floor. According to Polk, the passive-radiator coupling reproduces the low frequencies more efficiently than a simple port radiator, while the mass and size of the passive cone (called the “sub-bass” radiator) attenuate the higher frequencies, providing an 18-dB-per-octave rolloff matching the low-frequency rolloff of the satellites. Since each driver is connected to one of the stereo channels, the two channels are acoustically blended throughout the subwoofer’s operating frequency range (which contains virtually no directional information). Although the subwoofer’s response rolls off naturally above 170 Hz, the unit also contains a first-order low-pass filter to avoid wasting amplifier power above its operating range.