Can a modulatable graphic EQ be built with the current state of the DSP module?


Hi JUCErs,

I have built a graphic EQ with a bank of Peak and Shelf IIR filters from the DSP module.

So far I’ve only been using it without a realtime modulation (you change the cutoff on one of the filters, and it recomputes a clip of audio in the background).

Now I would like to use it realtime as an EQ on the wet signal of my plugin.

But it seems that the filters I’ve used don’t support smooth modulation of their cutoff frequency.

So I read what I could here in the forum and it seems that the StateVariableFilter is what I need for this purpose. But it currently supports only LP, BP and HP filter types and no Peak and Shelf.

My graphic EQ implements an algorithm for accurate overall frequency response shape and I still need to use those types of filters to achieve that. Are smooth-modulation Peak and Shelf filters in the Roadmap for the next release?

And before that - what filters can I use NOW to create a graphic EQ with smooth realtime modulation of cutoff? Can I use a cascading array of BP StateVariableFilters?

//cc: @IvanC