R-1.5

About the R-1.5

The Usher R-1.5 amplifier is engineered to drive any loudspeaker with a warm, tube-like sound signature. It features high-quality construction using metal film resistors, film capacitors, and high-power bipolar transistors designed by Motorola to handle sophisticated power and current demands. The amplifier includes a massive AC power transformer with a high-capacitive filtering system for pure sound reproduction. It uses Burr-Brown OPA2134P Sound Plus Series operational amplifiers and offers a bridging switch for mono block operation, terminals compatible with banana plugs and spades, optional balanced inputs, and large handles on the front and rear panels for easy handling. The R-1.5 is heavily biased into Class A operation, providing a rich, warm sound with excellent detail, depth, and bass. It is known for its robust build quality, substantial weight (37 kg), and large heat sinks for thermal management. The amplifier is capable of delivering 150 watts per channel into 8 ohms and 260 watts per channel into 4 ohms, with a damping factor greater than 175 and a frequency response from 20 Hz to 100 kHz (-3 dB). It is designed to be bridged easily to create powerful mono blocks delivering up to 400 watts into 8 ohms. The unit measures 18.9" x 18.9" x 8.9" (W x D x H) and weighs approximately 82 lbs (37 kg).