Technics AM/FM quad 4 channel stereo receiver model SA-8500X. From 1974 to 1976. Rated at 26 watts x 4 or 80 watts x 2. Features, three tape in/outputs front and rear, two phono inputs, one aux input front and rear, speaker selectors, high and low filters on/off, loudness on/off, FM muting on/off, CD-4 High-Blend on/off, volume and separate volume controls for left front and rear and right front and rear, separate bass, and treble controls, signal strength indicator, four power watt meters for front right/left and rear right/left and many more features.