- #1
foobag
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Hi Guys.
I have a question on the behavior of active filters (low/high/band) that are connected serially in multiple order magnitude.
For instance given 2 low pass filters.
Now I understand there exists a -6dB/octave cutoff, and generally f_o or the -3dB value is situated at the x-intercept of a graph showing frequency vs gain.
If there are multiple filters, such as 2, then I understand this changes to a -12dB/octave, and so forth as more filters are attached with the same resistor/capacitor values etc.
Now my question is let's say someone asks to find f_4, or f_10, generally how does one go about calculating this? If there was just one LPF with f_0 of 1000Hz, than f_2 is -6dB/octave so it would be half as much, am I correct? How does this apply to a 2 LPF design, would it be 1/4 as much?
I have a question on the behavior of active filters (low/high/band) that are connected serially in multiple order magnitude.
For instance given 2 low pass filters.
Now I understand there exists a -6dB/octave cutoff, and generally f_o or the -3dB value is situated at the x-intercept of a graph showing frequency vs gain.
If there are multiple filters, such as 2, then I understand this changes to a -12dB/octave, and so forth as more filters are attached with the same resistor/capacitor values etc.
Now my question is let's say someone asks to find f_4, or f_10, generally how does one go about calculating this? If there was just one LPF with f_0 of 1000Hz, than f_2 is -6dB/octave so it would be half as much, am I correct? How does this apply to a 2 LPF design, would it be 1/4 as much?