circa late 1960s Sound City Studio 20

Very Good condition, 7,5/10, has been checked by our tech and he notes: no codes on transformers, has been renovated thoroughly in the past with many components on the circuit board replaced, probably necessary, I replaced one ECC83, made for Dallas Arbiter Ltd London England, 3 channels (Mic 1, Mic 2 and Gram/Radio/Tape), 2 speaker outputs (one marked with a sticker 4 and one 15, perhaps ohms?), from online: This incredible sounding small tube amp was manufactured by Elpico, as the model AC88 amplifier