|After you open the monitor for BTWLPF, choose "View" -> "Scale
Put 5000 for "End Frequency" and -70 for "Gain Range".
Remember you set Cutoff Frequency 2000 and see the reduction ratio is -3dB at 2000Hz.
If you want its coefficients, please choose "Tools" -> "Save Coefficients" on the menu. The monitor window of BTWLPF (U_0) needs to be enabled.
See the coefficients, block diagram and transfer function.