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ln order to improve the limitation of the number of delay limitation the existing feedback delay network method and the inability to determine the sub-band reverberation time, this paper introduces a feedback delay network for artificial reverberation based on the Householder feedback matrix and Butterworth filler bank . The Householder feedback matrix can maximize the echo density, the choice of delay lines number is relatively free. The Butterworth filter bank is convenient for specifying the sub-band reverberation time. In the simulation experiment, The validity of The proposed method was verified by spectrogram, perceptual evaluation of speech quality, and subjective evaluation. [ABSTRACT FROM AUTHOR]

Feedback delay networks (FDNs) belong to a general class of recursive filters which are widely used in sound synthesis and physical modeling applications. We present a numerical technique to compute the modal decomposition of the FDN transfer function. The proposed pole finding algorithm is based on the Ehrlich-Aberth iteration for matrix polynomials and has improved computational performance of up to three orders of magnitude compared to a scalar polynomial root finder. The computational performance is further improved by bounds on the pole location and an approximate iteration step. We demonstrate how explicit knowledge of the FDN's modal behavior facilitates analysis and improvements for artificial reverberation. The statistical distribution of mode frequency and residue magnitudes demonstrate that relatively few modes contribute a large portion of impulse response energy. [ABSTRACT FROM AUTHOR]

Lossless Feedback Delay Networks (FDNs) are commonly used as a design prototype for artificial reverberation algorithms. The lossless property is dependent on the feedback matrix, which connects the output of a set of delays to their inputs, and the lengths of the delays. Both, unitary and triangular feedback matrices are known to constitute lossless FDNs, however, the most general class of lossless feedback matrices has not been identified. In this contribution, it is shown that the FDN is lossless for any set of delays, if all irreducible components of the feedback matrix are diagonally similar to a unitary matrix. The necessity of the generalized class of feedback matrices is demonstrated by examples of FDN designs proposed in literature. [ABSTRACT FROM PUBLISHER]