Emulation of Analog Filters in the Digital Domain

Poletti M. Emulation of Analog Filters in the Digital Domain. J Audio Eng Soc. 2026;74(1/2):50-60. doi:10.17743/jaes.2022.0239

@article{Poletti2026_23121,
  author = {Poletti, Mark},
  title = {{Emulation of Analog Filters in the Digital Domain}},
  journal = {Journal of the Audio Engineering Society},
  volume = {74},
  number = {1/2},
  pages = {50--60},
  year = {2026},
  month = feb,
  publisher = {Audio Engineering Society},
  doi = {10.17743/jaes.2022.0239},
  url = {https://doi.org/10.17743/jaes.2022.0239}
}

TY  - JOUR
TI  - Emulation of Analog Filters in the Digital Domain
AU  - Poletti, Mark
T2  - Journal of the Audio Engineering Society
J2  - J. Audio Eng. Soc.
VL  - 74
IS  - 1/2
SP  - 50
EP  - 60
PY  - 2026
DA  - 2026/02/10
DO  - 10.17743/jaes.2022.0239
UR  - https://doi.org/10.17743/jaes.2022.0239
PB  - Audio Engineering Society
LA  - en
AB  - Digital equalizers typically aim to emulate analog responses, and the finite digital bandwidth leads to a divergence from the analog response near the Nyquist frequency. This paper develops sets of low-pass, band-pass, and high-pass filters that minimize this divergence. The first set is developed using the matched z-transform with numerators designed to control the high-frequency behavior. The second set generalizes the bilinear transform filters to provide a closer match to the analog counterparts at high Q values. A symmetric parametric equalizer is also derived that generalizes previous designs. This equalizer is then modified to better match the analog filter response near the Nyquist frequency.
ER  -