I’ve just digitized a cassette via USB deck and the gain of the noise is -36. I need to increase the noise like Dolby S (analog noise reduction) and then using the actual noise reduction effect. If you have way to simulate Dolby S, tell here.
I’ve seen a plug-in for Dolby B… somewhere online… But I’ve never seen anything for “S”.
Since Dolby nose reduction is level dependent it has to be calibrated. There’s no “natural” or default calibration between magnetic tape levels and digital dBFS levels so you’d need a calibration tape. You MIGHT find a tape for B but I don’t know if the calibration levels are different for S.