I'm "playing" with filters, practicing the formula and trying to apply them to practical use cases. One of the things I'm trying to do is to aplify the signal that the filter passes through, but I don't want anything on the lower frequences coming through. Since filters do not block lower/higher frequencies but just makes them smaller, is there any way to block unwanted frequences completely or how would you approach the issue of only letting frequencies higher than let's say 100Khz through to the circuit you want the frequency to control. In other words, frequencies lower than 100Khz would be considered noise.
Is this "just" a game of averages where making the signal low enough that it has no real impact on the subsequent circuit?