(2nd order, 12 dB/octave, Lowpass)
R=4.7k-10 kΩ
<math>Ca=\frac {0.9076}{2\pi \times Fc \times R}</math>
<math>Cb=\frac {0.6809}{2\pi \times Fc \times R}</math>
Units: R [Ω], Cx [F], Fc [Hz]
