Specifications

Digidesign Plug-Ins Guide98
A Reverb Overview
Digital reverberation processing can simulate
the complex natural reflections and echoes that
occur after a sound has been produced, impart-
ing a sense of space and depth—the signature of
an acoustic environment. When you use a rever-
beration plug-in such as Reverb One, you are ar-
tificially creating a sound space with a specific
acoustic character.
This character can be melded with audio mate-
rial, with the end result being an adjustable mix
of the original dry source and the reverberant
wet signal. Reverberation can take relatively life-
less mono source material and create a stereo
acoustic environment that gives the source a
perceived weight and depth in a mix.
Creating Unique Sounds
In addition, digital signal processing can be used
creatively to produce reverberation characteris-
tics that do not exist in nature. There are no
rules that need to be followed to produce inter-
esting treatments. Experimentation can often
produce striking new sounds.
Acoustic Environments
When you hear live sound in an acoustic envi-
ronment, you generally hear much more than
just the direct sound from the source. In fact,
sound in an anechoic chamber, devoid of an
acoustic space’s character, can sound harsh and
unnatural.
Each real-world acoustical environment, from a
closet to a cathedral, has its own unique acous-
tical character or sonic signature. When the re-
flections and reverberation produced by a space
combine with the source sound, we say that the
space is excited by the source. Depending on the
acoustic environment, this could produce the
warm sonic characteristics we associate with re-
verberation, or it could produce echoes or other
unusual sonic characteristics.
Reverb Character
The character of a reverberation depends on a
number of things. These include proximity to
the sound source, the shape of the space, the ab-
sorptivity of the construction material, and the
position of the listener.
Reflected Sound
In a typical concert hall, sound reaches the lis-
tener shortly after it is produced. The original di-
rect sound is followed by reflections from the
ceiling or walls. Reflections that arrive within 50
to 80 milliseconds of the direct sound are called
early reflections. Subsequent reflections are called
late reverberation. Early reflections provide a
sense of depth and strengthen the perception of
loudness and clarity. The delay time between
the arrival of the direct sound and the begin-
ning of early reflections is called the pre-delay.
The loudness of later reflections combined with
a large pre-delay can contribute to the percep-
tion of largeness of an acoustical space. Early re-
flections are followed by reverberation and re-
petitive reflections and attenuation of the
original sound reflected from walls, ceilings,
floors, and other objects. This sound provides a
sense of depth or size.
Reverb One provides control over these rever-
beration parameters so that extremely natural-
sounding reverb effects can be created and ap-
plied in the Pro Tools mix environment.