If you double a frequency, it is the same note and octave up. If you cut a frequency in half, it is that note and octave down.
Most start at 20hz, which is (approx) an E.
Then 25hz, which is between an G and a G#
Then 31.5hz, which is between a B and a C
Every other slider is a multiple of those three frequencies. 40hz is an octave up from 20hz, 50hz is an octave up from 25hz, 63hz is an octave up from 31.5hz, and so on.
This means that you only ever really have control of those same three tones in all the octaves. Yes, you can make bigger curves by adjusting multiple sliders, but if you (for example) have a problem at 450 hz, you will have to dip both 400hz and 500hz in order to take care of it. This affects everything from 315hz to 630hz, when you really only need to dip a narrow band at 450hz.
It's kind of like doing heart surgery with a broadsword. A decent parametric EQ would allow you to build the complex curves at the precise frequencies you will need to accomplish your goal.