Designing Audio Effect Plugins in C++, 2nd Edition

Chapter 17Reverb Effects

Reverb effects 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. 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 long FIR filter. For large rooms, these impulse responses could be 5 to 10 seconds in length. In the mid 1990s, Gardner developed a hybrid system for fast convolution ...