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arXiv · 2509.21544

Real-time implementation of vibrato transfer as an audio effect

Abstract

An algorithm for deriving delay functions based on real examples of vibrato was recently introduced and can be used to perform a vibrato transfer, in which the vibrato pattern of a target signal is imparted onto an incoming sound using a delay line. The algorithm contains methods that computationally restrict a real-time implementation. Here, a real-time approximation is presented that incorporates an efficient fundamental frequency estimation algorithm and time-domain polyphase IIR filters that approximate an analytic signal. The vibrato transfer algorithm is further supplemented with a proposed method to transfer the amplitude modulation of the target sound, moving this method beyond the capabilities of typical delay-based vibrato effects. Modifications to the original algorithm for real-time use are detailed here and available as source code for an implementation as a VST plugin. This algorithm has applications as an audio effect in sound design, sound morphing, and real-time vibrato control of synthesized sounds.

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BibTeXRIS

Jeremy Hyrkas. 2025-09-25. Real-time implementation of vibrato transfer as an audio effect. https://arxiv.org/abs/2509.21544

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