ATKAutoSwell Free Vst Compressor Plugin. a free plug-in for Mac OS X and Windows that is made to lower the output sound after it crosses the threshold. ATKAutoSwell does work similar to a compressor, but instead of only acting on the signal precedent the threshold, it applies the gain transfer function to the complete signal. So above the threshold, you are able to make the output signal lower.
This mono autoswell plugin implements a ratio to the global gain of a signal one time it is higher than a given threshold. We can say that opposing to a compressor where the power of the signal will never go lower than the threshold, for AutoSwell, it is capable. For good operation, it may become the best compressor plugin for vocals or may be the best mastering compressor plugin.