The easy to use Pole-Zero editor (P-Z editor) of ASN Filter Designer

The P-Z (pole-zero) editor provides designers with a comprehensive and easy to use pole-zero editor. Together with  useful options not commonly found in other filter design software. How does it work?

Zooming in/out and panning

As with the frequency response chart, you may zoom in and out into any area by using the mouse wheel.

Scrolling may be achieved by depressing the left mouse button and dragging the chart in any direction.

Locked filter gain

The Locked Filter Gain automatically calculates the filter gain required in order to set the magnitude spectrum to the specified gain in dB at the specified frequency. After clicking on the   button, a yellow padlock will appear on the frequency response chart at the specified location.

The P-Z chart editor is a fully interactive pole-zero editor allowing designers to zoom, pan and graphically fine-tune designs to their exact requirements.

The frequency response chart is updated in real-time allowing for instant evaluation of the new pole-zero positions.

double click on the axes  line markers to reset the chart view.

Filter gain

The exact Locked Filter Gain value will appear in the filter summary, and is automatically included into the filter implementation via the signal analyser.

Pole-zero properties window

You may get the specific properties of a pole or zero by double-clicking on it in the P-Z chart.

Locking the magnitude or frequency results in orange guide lines (see right) appearing on the chart. This is functionality is extremely useful for locking a dimension when modifying pole/zero position with the mouse.

Section number and section lock

section number and lock

Section number

This allows you to highlight the pole and zeros of a specific section in the H1 filter:

  • For FIR filters or single section IIR filters: the section number will always be equal to 1.
  • For biquad IIR filters: this will be a list of all the biquad sections in the filter cascade

Section lock

Clicking on the section lock, allows you to focus on a specific section by highlighting all of the poles-zeros of the selected section number (Section No) and minimising the rest.