understanding the modulation eq filters

Hey, I have a hard time understanding, how the Eq filters in the modulation settings work. I assume they are bellcurve shaped or something, but what does the db stand for. Thought -6/15 db would maybe dampen some frequencies, but at low fq and Q values it even gets very noisy… So maybe could someone enlighten me, what would the filtercurves look like at different fq/Q values for those? It is just that I get very interesting sounds out of those and would like to understand why :)