can someone tell me if pretty much all IIR filters have a tan(fc * PI / 2) response for the cutoff coefficient?
more specifically, does this simple 6 dB/oct Butterworth filter have a cutoff of 1/2 the Nyquist frequency?
constants:
c = tan(0.5 * PI / 2)
loop:
out += c * (in - out)
loop (equivalent):
out = c * in - c * out
Lorewegian 📚 /
npub1ds…ce3jc
2023-05-19 08:06:17
Author Public Key
npub1dsr8aceet06f6g2sgdyajh6lla0d7s0vvj4gj5fnf6yfmwhcuv0sdce3jcPublished at
2023-05-19 08:06:17Event JSON
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"content": "can someone tell me if pretty much all IIR filters have a tan(fc * PI / 2) response for the cutoff coefficient?\n\nmore specifically, does this simple 6 dB/oct Butterworth filter have a cutoff of 1/2 the Nyquist frequency?\n\nconstants:\nc = tan(0.5 * PI / 2)\n\nloop:\nout += c * (in - out)\n\nloop (equivalent):\nout = c * in - c * out",
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