# Inverse a frequency response

I haven't recorded a precise impulse response, but I have carefully written the attenuation/boost of a recording chain for every third of octave:

20 Hz,   25 Hz, 32 Hz, 40 Hz, 50 Hz, 64 Hz, 80 Hz, ..., 640 Hz, 806 Hz, 1016 Hz, 1280 Hz, ...
-1 dB, -1.3 dB, -2 dB, ..., +2 dB, +2.5 dB, +1.5 dB, ...


How to inverse this frequency response? I can do it with an equalizer in any audio editor, but how would you do it with code? (e.g. Python)

How to make use of this list [-1, -1.3, -2, ..., 2, 2.5, 1.5, ...] ?

• Well, you use or implement&use an equalizer in Python. But you probably already know that – so, what's your question, can you ask it more precisely? – Marcus Müller Jan 21 '17 at 15:34
• Well I don't know how to do this with dB specifications for each frequency, any idea about implementation, with minimal phase modification? – Basj Jan 21 '17 at 17:34
• well, as you said, you can adjust an equalizer to inverse these effects, given you have an equalizer that does this fine frequency resolution. So I really don't know exactly what you want me to explain: How to design an equalizing filter for especially these numbers, or how to design the functional equivalent of your graphical EQ, or how to convert dB into linear? – Marcus Müller Jan 21 '17 at 17:47
• dB/linear is ok, the question for me is how to design such an equalizing filter (with 3 specs per octave) and how to implement it using a dsp library (python numpy for example or pseudo code) – Basj Jan 21 '17 at 18:10