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W. Pirkle, "Resolving Delay-Free Loops in Recursive Filters Using the Modified Härmä Method," Paper 9194, (2014 October.). doi: W. Pirkle, "Resolving Delay-Free Loops in Recursive Filters Using the Modified Härmä Method," Paper 9194, (2014 October.). doi:
Abstract: Resolving delay-free loops in recursive filter structures has been a longstanding problem approached in several different ways including signal flow graph manipulation [1], [2] and more recently with Zavalishin’s instantaneous response technique [3],[4]. Härmä demonstrates a method for resolving delay-less loops in recursive filter structures [5] but the technique is limited to a specific generic loop topology in which the feedforward branch does not implement signal processing; all processing is implemented in one or more delay-less feedback loops. We modify Härmä’s method to accommodate filter processing in the feedforward branch and provide a step-by-step method to resolve delay-less loops in recursive filter structures. We conclude with examples including a new method of synthesizing fourth order filters.

@article{pirkle2014resolving,
author={pirkle, will},
journal={journal of the audio engineering society},
title={resolving delay-free loops in recursive filters using the modified härmä method},
year={2014},
volume={},
number={},
pages={},
doi={},
month={october},} @article{pirkle2014resolving,
author={pirkle, will},
journal={journal of the audio engineering society},
title={resolving delay-free loops in recursive filters using the modified härmä method},
year={2014},
volume={},
number={},
pages={},
doi={},
month={october},
abstract={resolving delay-free loops in recursive filter structures has been a longstanding problem approached in several different ways including signal flow graph manipulation [1], [2] and more recently with zavalishin’s instantaneous response technique [3],[4]. härmä demonstrates a method for resolving delay-less loops in recursive filter structures [5] but the technique is limited to a specific generic loop topology in which the feedforward branch does not implement signal processing; all processing is implemented in one or more delay-less feedback loops. we modify härmä’s method to accommodate filter processing in the feedforward branch and provide a step-by-step method to resolve delay-less loops in recursive filter structures. we conclude with examples including a new method of synthesizing fourth order filters.},}

TY - paper
TI - Resolving Delay-Free Loops in Recursive Filters Using the Modified Härmä Method
SP - EP -
AU - Pirkle, Will
PY - 2014
JO - Journal of the Audio Engineering Society
IS -
VO -
VL -
Y1 - October 2014 TY - paper
TI - Resolving Delay-Free Loops in Recursive Filters Using the Modified Härmä Method
SP - EP -
AU - Pirkle, Will
PY - 2014
JO - Journal of the Audio Engineering Society
IS -
VO -
VL -
Y1 - October 2014
AB - Resolving delay-free loops in recursive filter structures has been a longstanding problem approached in several different ways including signal flow graph manipulation [1], [2] and more recently with Zavalishin’s instantaneous response technique [3],[4]. Härmä demonstrates a method for resolving delay-less loops in recursive filter structures [5] but the technique is limited to a specific generic loop topology in which the feedforward branch does not implement signal processing; all processing is implemented in one or more delay-less feedback loops. We modify Härmä’s method to accommodate filter processing in the feedforward branch and provide a step-by-step method to resolve delay-less loops in recursive filter structures. We conclude with examples including a new method of synthesizing fourth order filters.