Fifty Years of Artificial Reverberation

TLDR

Artificial reverberation algorithms, first proposed in the 1960s, have become a staple of music production since the 1970s, are now applied to game audio, VR, and acoustic design, and with increasing computing power are moving toward real‑time use and analog‑unit emulation. The article reviews digital artificial reverberation approaches and presents a case study of an improved parametric spring reverberator model. The review categorizes artificial reverberation into delay networks, convolution-based algorithms, and physical room models, and details an improved parametric spring reverberator model.

Abstract

The first artificial reverberation algorithms were proposed in the early 1960s, and new, improved algorithms are published regularly. These algorithms have been widely used in music production since the 1970s, and now find applications in new fields, such as game audio. This overview article provides a unified review of the various approaches to digital artificial reverberation. The three main categories have been delay networks, convolution-based algorithms, and physical room models. Delay-network and convolution techniques have been competing in popularity in the music technology field, and are often employed to produce a desired perceptual or artistic effect. In applications including virtual reality, predictive acoustic modeling, and computer-aided design of acoustic spaces, accuracy is desired, and physical models have been mainly used, although, due to their computational complexity, they are currently mainly used for simplified geometries or to generate reverberation impulse responses for use with a convolution method. With the increase of computing power, all these approaches will be available in real time. A recent trend in audio technology is the emulation of analog artificial reverberation units, such as spring reverberators, using signal processing algorithms. As a case study we present an improved parametric model for a spring reverberation unit.