: A classic freeware alternative that emulates the hardware's looks and sonic characteristics, though it may be harder to find on official developer sites today. Comparison Table: CLA-2A vs. Free Clones Key Free Feature Opto Emulation Vocals, Bass Side-chain filter AdHd Leveling Tool Tube Leveling Transparent Vocals Adjustable Attack/Release Warmth, Glue Simplified workflow CA-2A (Cakewalk) Opto Emulation General Mixing Highly accurate (if you have an old copy) set up a side-chain with these compressors, or are you looking for installation guides for a specific DAW?