The Rotel RC-850 is a solid-state stereo control preamplifier from the late 1980s (circa 1988), designed to work with both Moving Magnet (MM) and Moving Coil (MC) phono cartridges. It features four line-level inputs, two tape loops, and tone controls (bass/treble). The unit is known for high-quality, low-noise phono performance, making it an excellent, versatile choice for vinyl enthusiast