What is the main advantage of using an op-amp audio filter over a passive LC audio filter?

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The key idea is that active filters using an op-amp can provide actual gain instead of just loss. An op-amp stage is powered, so the filter can amplify the signal as it shapes its frequency response. This not only helps compensate for any attenuation in the network, but also lets the filter buffer the signal so the response doesn’t change when the source or the load connected to the output varies. Passive LC filters, on the other hand, can only attenuate and their performance is strongly affected by what’s connected to them, making it harder to achieve steep or precise responses without sacrificing level. The other statements aren’t the main advantage: op-amps aren’t inherently immune to vibration or temperature drift, and while there are many op-amp options, the defining benefit in this comparison is the ability to provide gain and isolation, not merely the availability of different voltage or frequency ranges.