The equalizer is a real-time audio effect to improve or edit audio by adjusting its frequencies.
Here is how to use it:
1) Click on the three dots next to the track's name you want to apply the equalizer.
2) Select Show Options.
3) A toolbar will pop out on the right-hand side; click on Add Effect and then Equalizer.
4) Adjust the frequencies as needed.
5) If you need to turn it off or delete it, you can do so by turning the toggle off or clicking on Delete next to the Equalizer.