HifiBerry DAC/dsp implementation with dsptools

I recently built a raspberry pi 4 and have attached the hifiberry dac/dsp hat.
4gb rpi4, raspbian latest, all seems working fine until I play with dsptools.

The current doc at github lists commands that are simply out of date.
E.G. dsptoolkit remove-iir-filters is actually dsptoolkit clear-iir-filters. My first attempt removed every tone above 300hz. It went well.

Does anyone have a link to a more detailed explanation/hands on/video. A list of things you’ve all learned not to do. Things to do. When to use dsp via hardware and when by software. Looking to stand on the shoulders of those who came before me so to speak.

Thank you.

I guess I’ll just keep whacking at it. Not sure that big balloon on the left end is where I wish to be.
before corrections in green, after in red.