Each of the two channels features an additional transformer that can be switched into the signal chain after the mix stage. In principle, these are classic output transformers, but here they are not used for balancing and galvanic isolation, but as an additional means of sound shaping.
If you like to add that certain amount of ‚iron‘ to your sound, just push the transformer button and there you are. Because of the mastering approach of the alpha compressor, this feature is much more of a subtle audio shaping feature than a glaring sound effect.
In stereo mode, the buttons for both channels should be activated or deactivated at the same time. Depending on the source material and personal taste, you can, however, add the transformer sound to single channels when working in M/S mode.