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Reverb eects overview
You can use reverb eects to simulate the sound of acoustic environments such as rooms,
concert halls, caverns, or an open space.
Sound waves repeatedly bounce o the surfaces—walls, ceilings, windows, and so on—of any
space, or o objects within a space, gradually dying out until they are inaudible. These bouncing
sound waves result in a reection pattern, more commonly known as a reverberation (or reverb).
The starting portion of a reverberation signal consists of a number of discrete reections
that you can clearly discern before the diuse reverb tail builds up. These early reections are
essential in human perception of spatial characteristics, such as the size and shape of a room.
Signal Discrete
reflections
Diffuse reverb tail
Time
Reflection pattern/ reverberation
Amplitude
Plates, digital reverb eects, and convolution reverb
The rst form of reverb used in music production was actually a purpose-built room with hard
surfaces, called an echo chamber. It was used to add echoes to the signal. Mechanical devices,
including metal plates and springs, were also used to add reverberation to the output of musical
instruments and microphones.
Digital recording introduced digital reverb eects, which consist of thousands of delays of
varying lengths and intensities. The time dierences between the original signal and the arrival
of the early reections can be adjusted by a parameter commonly known as predelay. The
average number of reections in a given period of time is determined by the density parameter.
The regularity or irregularity of the density is controlled with the diusion parameter.
Today’s computers make it possible to sample the reverb characteristics of real spaces,
using convolution reverbs. These room characteristic sample recordings are known as
impulse responses.
Reverb eects
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