Woodstock Audio Waveform Compressor

Waveform Compressor by Woodstock Audio is the free compressor I’d hand to anyone who is still trying to figure out what compression actually does to a signal. The interface is built around a GPU-accelerated waveform view that shows the input and output signals on top of each other, with a gain reduction line and a threshold line that moves as you turn the threshold knob. You can see which peaks are going to get caught before you commit, and the Delta Solo button lets you listen to only the part of the signal the compressor is removing.

That feature alone is a serious learning shortcut because you can hear exactly what the compressor is removing. The plugin offers two modes. Regular is a feedforward VCA design with full control over threshold, ratio, attack (down to 20 microseconds), release, and knee. On the other hand, optical mimics the program-dependent response of LA-style hardware. The attack speeds up as the signal stays hot, and the release runs in stages.

The sidechain section has a built-in HPF and accepts an external trigger. You also get ten presets that cover analog character, mix bus, and mastering starting points.