A Tilt Filter in a Servo Loop

Lazzaro J, Wawrzynek J. A Tilt Filter in a Servo Loop. In: AES Convention 133. Audio Engineering Society; 2012. Paper 8692. Available from: https://aes.org/publications/elibrary-page/?id=16435

@inproceedings{Lazzaro2012_16435,
  author = {Lazzaro, John and Wawrzynek, John},
  title = {{A Tilt Filter in a Servo Loop}},
  booktitle = {AES Convention 133},
  note = {Paper 8692},
  year = {2012},
  month = oct,
  publisher = {Audio Engineering Society},
  url = {https://aes.org/publications/elibrary-page/?id=16435}
}

TY  - CPAPER
TI  - A Tilt Filter in a Servo Loop
AU  - Lazzaro, John
AU  - Wawrzynek, John
T2  - AES Convention 133
M1  - Paper 8692
PY  - 2012
DA  - 2012/10/06
UR  - https://aes.org/publications/elibrary-page/?id=16435
PB  - Audio Engineering Society
LA  - en
AB  - Tone controls based on the tilt filter first appeared in 1982, in the Quad 34 Hi-Fi preamp. More recently, tilt filters have found a home in specialist audio processors such as the Elysia mpressor. This paper describes a novel dynamic filter design based on a tilt filter. A control system sets the tilt slope of the filter, in order to servo the spectral median of the filter output to a user-specified target. Users also specify a tracking time. Potential applications include single-instrument processing (in the spirit of envelope filters) and mastering (for subtle control of tonal balance). Although we have prototyped the design as an AudioUnit plug-in, the architecture is also a good match for analog circuit implementation.
ER  -