The magnitude response of matched z-transform (MZT) filters deviates from the response of analog filters in a relatively gradual fashion. The error can be minimized by adding zeros to an all-pole filter or by shifting the position of the poles or zeros in a biquadratic filter. A set of efficient closed form algorithms is presented which provide optimum coefficients. The resulting filters (dubbed “MZTi”) display excellent agreement with the analog target filters, both in their magnitude and phase responses.