Urei 509 EQ

This is an EQ module from an old Universal Audio console. It is a switched gain, switched frequency, LC/RC filter. We wired it as a passive filter with a make-up gain amp (John Hardy 990 Op Amp). The gain controls are reversed, because of this. It’s a dead simple eq that has 2 bands (bass and treble), 4 selectable frequencies each (in cut only), and 2 shelves (boost only). So far, it has been handy in adding top end to ribbon mics, and bottom end to kick drum mics.