Tube / Vintage Compressor - Input

I´ve just updated to Cubase Elements 9 and I see there are two more compressors in comparison with one I used before in LE 6 - Tube and Vintage Compressors. But I´m not sure what does “Input” knob do. In the Operational Manual it is written: Input - Determines the compression amount. The higher the input gain, the more compression is applied.
Is this “Input” knob an analogy of “Ratio” in a compressor? If yes, can it be said, for example, that +3dB on “Input” on this Tube or Vintage compressor performs a compression 3:1 ?


The tube compressor is loosely modeled on a LA2A, ie compression is material dependent, the harder you drive the input, the more compression (and distortion) you’ll get.

The vintage compressor is a 1176 clone, there are zillions of articles and videos on LA2As and 1176s. Pretty much what applies to those compressors applies to the two Steinberg offerings.