I'm working on a tutorial about all this filter theory in depth right now that makes it accessible to musicians, but in portuguese only.
but long story short, if you have no idea, maybe you shouldn't bother with it :)
what you should know is that you can have lots of filter types with a biquad system, you only need to generate the right coefficients. There are some externals that do that for you, some are in Pd-Extended, check the attaches file. In max/msp, the filtergraph object will do that kind of thing too.
cheers