I'm trying to limit audible bandwidth outside of 5kHz to 9kHz range. Just to get started I designed a passive band-pass filter successfully. Because I would like to get more aggressive attenuation and use filter with audio amplifier I found that multiple feedback narrow band-pass filter design can be used. I used online tool to calculate values for necessary components
I built this circuit by using LM318N op-amp. I used Analog Discovery 2 to generate sine wave from 0Hz to several hundred kHz and used scope/spectrum tool to observer output. Problem is that this circuit did not manage to attenuate output signal. I noticed that I get almost the same result even when op-am is not powered. Might be it is because of those feedback components? If that is the case how can this design even work? I'm very much a beginner and guidance would be much appreciated!

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