I'm not sure if this should be this way, maybe someone can explain. I'm pretty useless when it comes to the science behind synthesis!
When using the LFO on the filter, the higher I have the cutoff level, the less obvious the LFO effect (to the point where when the cutoff is near full, the LFO's affect isn't noticeable). The best way I can describe it is that when the cutoff is low, the LFO's affect seems stronger and defined, and the cutoff knob acts almost like a 'release' control - so when its totally full, there is no definition from the LFO waveform.
Any explanation of the link would be appreciated, thanks!