Frequency-Dependent Schroeder Allpass Filters
Source abstract
Abstract
Since the introduction of feedforward–feedback comb allpass filters by Schroeder and Logan, its popularity has not diminished due to its computational efficiency and versatile applicability in artificial reverberation, decorrelation, and dispersive system design. In this work, we present an extension to the Schroeder allpass filter by introducing frequency-dependent feedforward and feedback gains while maintaining the allpass characteristic. By this, we directly improve upon the design of Dahl and Jot which exhibits a frequency-dependent absorption but does not preserve the allpass property. At the same time, we also improve upon Gerzon’s allpass filter as our design is both less restrictive and computationally more efficient. We provide a complete derivation of the filter structure and its properties. Furthermore, we illustrate the usefulness of the structure by designing an allpass decorrelation filter with frequency-dependent decay characteristics.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: Acoustic Wave Phenomena Research · Speech and Audio Processing · Advanced Adaptive Filtering Techniques
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Affiliations
Department of Signal Processing and Acoustics and Department of Media, Aalto University, 02150 Espoo, Finland
References (26)
Show source-provided references
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