Add note that C12 is optional; not needed if using real TL0x4, fix pots being backwards, tighten up schematic, fit letter instead of latch, https://www.neutrik.com/en/product/nc3fah-0 A Series, 4 pole chassis connector, black D-size flange, self tapping screw holes (A-screw), horizontal PCB mount, black chrome shell, https://www.neutrik.com/en/product/nc5fbh-b B Series, 3 pole female XLR receptacle, grounding.