Add distortion to the sound source. The compression solution provides extremely fast attack time, a lookahead parameter, uninterrupted ratio, parallel compression, low and high cut filters detection, stereo with synchronized gain reduction, and external side chain.
Many "modeled" compressors are nothing more than futile attempts to get an off-the-shelf algorithm to match its hardware counterpart by tweaking a few parameters like the knee and attack/release times. But anyone who has worked with hardware compressors knows that there must be more to it. And there is.
The heritage of analog compressors very much showcases the history of electronics in the previous century. It's the deficiencies of the different designs and components that give each unit its unique character, and what started out as technical limitations have now become sought-after sounds. Simply approximating the most apparent features is not enough to capture this uniqueness. It takes a model of great complexity and accuracy to make a digital replica sound like the original with all settings and inputs.
When creating FET Compressor, Softube set out to make the most accurate emulation of the most famous solid state compressor. Instead of modeling individual features and putting them together digitally we have modeled the unit in its entirety: input and output stages, gain reduction feedback loops, bias differences of different transistors, etc. It's been by far the hardest project we have taken on, but we feel that the result speaks for itself. And hopefully it will be easier to do it the next time (yeah right).