Freq is an EQ that makes mixing faster. Double-click the graph to add a band, drag to set frequency and gain, scroll to change the width. The analyser shows the spectrum before and after, so you see right away what's happening to the sound. Every band can work on stereo, left, right, mid or side. Dynamic mode turns a band down only when needed — perfect for a boxy vocal, harsh cymbals or a boomy bass. For mastering and Mid/Side work switch to Linear Phase: the same curve with no phase shift (your DAW compensates the latency).