Interested in experimenting with some IIR filters from this site...

www.schwietering.com/jayduino/filtuino/

Is this the process?

1) Create a library for the filter function(s). 2) Define filter type and calculate coefficients from the above site. 3) Copy the generated code to the created library. 4) Add library function(s) calls to sketch. 5) Run the sketch and evaluate results.

If only interested in a few known frequencies and frequency bands, does anyone know how efficient IIR filters are relative to FFT/FHT? Since IIR is much more frequency-tailor-able, unneeded bin data isn't calculated like with FFT/FHT.