MClass EQ improvements
RTA displayed behind M-Class Equalizer Filter graph in a darker red.
The RTA graph should show the post-filtered signal.
A switch on the low shelf that changes it to a high-pass filter
A switch on the high shelf that changes it to a low-pass filter.
When the shelves are in pass mode the Q knob changes the slope depth of the filter. The filter slope should be able to be smoothly warped between -6dB/Octave to -60dB/Octave, using a floating point multiplier, so that you might have a slope that is not strictly an integer multiple of 6.
Remove the cutoff frequency limits so that you can set your shelves or your pass modes to whatever frequency. I suppose in order to do this well, you'll need to change the way the audio buffer is filtered to ensure that there is no audible digital stepping.
these are my thoughts, thanks for listening!