In the explanatory steps of this brief overview of mixing and mastering, we have now already traversed the dimensions of volume and frequency spectrum. They can be easily distributed in the visualization on a surface in height and width. However, with this we have also exhausted this visualization.
Another basic function like saturation can only be traced with listening experiences and their description. In general, this can perhaps be described as a manipulation of ‘density’ and ‘sound texture’ – depending also on the effects used in detail, which of course differ from each other. In a further metaphorical comparison, one can speak, among other things, of a ‘roughening’ or ‘plasticizing’ of the sound. The number of plug-ins for this – like all the others – is now large. The origin of these effects is a sound difference that arises between purely digital and thereby rather low-noise recording techniques compared to physical audio tapes of earlier times. It is still practiced today, depending on one’s preferences, to record tracks onto tape and play them back even after the fact. Many of the plugins refer to tape recorders by their names and/or design or even emulate special models of this hardware.
Holger Steinbrink explains it here for KEYS in German:
Here are three more tutorials on the basics of saturation from Musician on a Mission, Sage Audio, and Warren Huart of Produce Like A Pro: