This applet is a tool showing various representations of digital filters. You can enter up to 6 feed-forward and feedback coefficients which get represented in the following ways:
- Frequency response (magnitude and phase)
- Phase response
- Difference equation
- Transfer function
- Pole-zero plot
- Block diagram
Coefficients can be smoothly changed by clicking and dragging the coefficient box. Finally, white noise can be fed through the filter to hear its effect in action.