Audio EQ Cookbook for HP 15c CE 1

I have just seen that there is another three software pacs available: made by Pepín Torres, the first of them is Audio EQ Cookbook for HP 15c CE. I will mention the other two (also by Pepín) in the following days.

You can find it here (as well as the others too): https://www.hpcalc.org/search.php?query=HP15c&other=1

From the manual:

What is it?

This software pac calculates all the filters coefficients and related parameters as defined in the classic document Cookbook formulae for audio equalizer biquad filter coefficients.

Who is this for?

This software pac is for any audio enthusiants, audio engineers, or software engineers that need to generate the coefficients for any of the 9 different filters in the cookbook (when there is no computer in sight). Furthermore, this pac also calculates the complex frequency response of any of the 9 filters at any arbitrary frequency fx. One use-case would be to generate the coefficients of a filter with center frequency f0 and calculate the complex response for a set of frequencies fx (think of being able to plot the response by sampling at different fx frequencies). Another use-case would be to run this program for a set of filters with different center frequencies f0 and evaluate each filter at a fixed fx to understand the gain/phase contributions of each filter at fx (think of an EQ with multiple bands that overlap fx).