A Generalization of the Biquadratic Parametric Equalizer

Christensen KB. A Generalization of the Biquadratic Parametric Equalizer. In: AES Convention 115. Audio Engineering Society; 2003. Paper 5916. Available from: https://aes.org/publications/elibrary-page/?id=12429

@inproceedings{Christensen2003_12429,
  author = {Christensen, Knud Bank},
  title = {{A Generalization of the Biquadratic Parametric Equalizer}},
  booktitle = {AES Convention 115},
  note = {Paper 5916},
  year = {2003},
  month = oct,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=12429}
}

TY  - CPAPER
TI  - A Generalization of the Biquadratic Parametric Equalizer
AU  - Christensen, Knud Bank
T2  - AES Convention 115
M1  - Paper 5916
PY  - 2003
DA  - 2003/10/06
UR  - https://aes.org/publications/elibrary-page/?id=12429
PB  - Audio Engineering Society
LA  - en
AB  - An efficient implementation of parametric equalizers is a cascade of biquadratic filter sections. Traditionally, a section operates in one of 3 operating modes offering Low Shelf, Bell Shaped or High Shelf families of responses. In either mode, each section offers 3 user parameters: Boost/cut gain G, corner frequency fc and bandwidth/slope Q. This paper describes the derivation and implementation of a new 4th user parameter, Symmetry, producing a smooth transition between the 3 above mentioned operating modes while retaining the meaning of the 3 conventional user parameters. All degrees of freedom in the bi-quadratic filter blocks are utilized. Therefore an inverse mapping exists, converting arbitrary (e.g. computer generated) biquadratic coefficient sets back into meaningful EQ parameters allowing further human interpretation and adjustment.
ER  -