the feeling of "progressive ratio" in most vari-mu's come from the way we usually try to control the less-than-linear gain-vs-current behavior of remote cutoff tubes. This makes it hard to set sharply-exact ratios - and most often we fix this by adding a soft knee to the compression onset.

That said, the Threshold function is simply the sidechain's AC gain before rectification, and Ratio is the DC gain of the sidechain signal post rectification AND soft-knee/threshold voltage constant

The G22's ratios are "real" in the sense that they span all the way from 1:1 (no-op, at full CCW) to somewhere around inf:1 (and often a bit beyond). And yes, the soft knee results in higher ratios at large transgressions of the threshold value than smaller ones..

First and foremost it's a unit that rewards a "take a minute to listen"- approach to settings: With hands on, you'll find that it behaves much more intuitively than what can be conveyed by technical descriptions.

I hope this helps..?

Jakob Erland
(who has commercial interests in this)