Model/Circuit Number: Years of Production: 1987 – 1993 Era: Configuration: Piggyback Controls: Black, forward facing w/ white labels, controls numbered 1 – 10 Knobs: red (87-90) or black (90-93), unnumbered Faceplate Front: Vol, Treb/Boost, Mid/Boost, Bass – Ch 1 In, Ch 1 In – Ch 2 In, Ch 2 In – Gain, Treb/Boost, Mid/Boost, Bass/Boost, [...]