This paper presents the time variant vectored comb filter. It is an extension of the feedback delay network to time variant and nonlinear domains. Effects such as chorus and flanger, tap delay and pitch shifter are examined in the context of the feedback scheme. Efficient implementation of a stateless vectorizable LFO for modulation purposes is presented, along with a recursive formulation of the Hadamard matrix multiplication. The time variant comb filter is examined in various effect settings, and presented with source code and sound examples.

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This paper describes the implementation of a recently introduced parallel graphic equalizer (PGE) in a heterogeneous way. The control and audio signal processing parts of the PGE are distributed to a PC and to a signal processor, of WaveCore architecture, respectively. This arrangement is particularly suited to the algorithm in question, benefiting from the low-latency characteristics of the audio signal processor as well as general purpose computing power for the more demanding filter coefficient computation. The design is achieved cleanly in a high-level language called Kronos, which we have adapted for the purposes of heterogeneous code generation from a uniform program source.

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