PreSonus AudioBox 44VSL - Manual (Page 72)

68
PreSonus AudioBox ™ 22/44VSL
Ov
er
view
Hook
up
Connec
ting
to a
Comput
er
Sof
tw
ar
e: V
irtual
StudioLiv
e
SL Remot
e,
and S
tudio O
ne Ar
tist
Tut
orials
Technical
Informa
tion
Troubleshooting
and W
arr
an
ty
5 Tutorials
Tut
orials
5.5 Digital Effects
5.5 Digital Effects
VSL includes two stereo effects processors that feature the two most
common type of effects in use for live sound: reverb and delay.
Studio One Artist also includes an assortment of time-based and modulation
effects. The following is a brief description of how each type works.
5.5.1 Reverb
Reverberation —or reverb, as it is more commonly known—is perhaps the most
widely used effect. Natural reverb is created by sound waves reflecting off of a surface
or many surfaces. For example, when you walk across the wooden stage in a large
hall, thousands of reflections are generated almost instantaneously as the sound
waves bounce off the floor, walls, and ceilings. These are known as early reflections,
and their pattern provides psycho-acoustic indications as to the nature of the space
that you are in, even if you can’t see it. As each reflection is then reflected off of more
surfaces, the complexity of the sound increases, while the reverb slowly decays.
The reason for the widespread use of reverb in audio recording is fairly self-evident:
human beings don’t live in a vacuum. Because our brains receive cues about the
nature of the space around us based partially on audio reflections, a sense of space
makes an audio recording sound more natural and, therefore, more pleasing.
The following parameters can usually be adjusted in a reverb effect:
• Decay. Decay is the time required for the reflections (reverberation) to die away.
In most modern music production, reverb decay times of between one and
three seconds are prevalent. A reverb setting with strong early reflections and
a quick decay are a great way to create a stereo effect from a mono source.
• Predelay. Predelay is the time between the end of the initial sound and the
moment when the first reflections become audible. Imagine you’re back on that
stage in a large music hall. This time you stand on the very edge of the stage
and shout “Hello world!” toward the center of the hall. There will be a brief pause
before you hear the first noticeable reflections of your voice because the sound
waves can travel much further before encountering a surface and bouncing
back. (There are closer surfaces, of course—notably the floor and the ceiling just
in front of the stage—but only a small part of the direct sound will go there, so
those reflections will be much less noticeable.) Adjusting the predelay parameter
on a reverb allows you to change the apparent size of the room without
having to change the overall decay time. This will give your mix a little more
transparency by leaving some space between the original sound and its reverb.
• HF and LF decay. The types of surfaces in a space also affect the sound.
Carpet and soft furnishings will absorb more high-frequency waves,
thereby reducing the high-frequency decay time, while hard surfaces
such as tile or stone reflect sound extremely well, resulting in a “brighter”
ambience. Similarly, the high-frequency (HF) and low-frequency (LF)
decay time allow you to adjust the “brightness” or “darkness” of the
reverb, enabling you to better emulate these environmental factors.