Designing Audio Effect Plug-Ins in C++

CHAPTER 11

Reverb Algorithms

Reverb algorithms might represent the Holy Grail of audio signal processing. They have an appeal that seems universal, perhaps because we live in a reverberant world. Our ears are time-integrating devices that use time domain cues and transients for information, so we are sensitive to anything that manipulates these cues. In this chapter, we discuss reverb algorithms as applied mainly to room simulation. There are two general ways to create the reverberation effect:

•  Reverb by direct convolution—the physical approach.

•  Reverb by simulation—the perceptual approach.

In the physical approach, the impulse response of a room is convolved with the input signal in a large finite impulse response (FIR) filter. For large ...