Equalizer circuit diagram supplied as a 263 KB PDF. The file name only says equalizer and gives no brand, model or board reference, so it cannot be tied to a particular amplifier or mixer. A tone-control or graphic equalizer schematic helps when tracing op-amp stages, checking filter capacitor values and following the signal path from input to output. Open it in any PDF viewer and compare the stage layout and supply voltages with the unit on the bench before trusting the values.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @gunvantrathore. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.