Studiomaster Logic-12 schematic, a compact 552 KB PDF. Studiomaster is a British maker of mixing consoles and powered mixers, and the Logic name refers to one of its products; what sections the drawing covers is not stated in the name. Technicians use such diagrams to trace channel strips, mix buses, power supply rails and output stages when chasing noise, dead channels or hum. Check that the unit's model label and board markings match before relying on component values or connector pinouts.
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