Digital Effects; Reverb - PRESONUS STUDIOLIVE 24.4.2 Owner's Manual

Owner's Manual

Digital Effects

8.6

8.6.1 Reverb

The StudioLive includes a stereo effects processor that features the two most
common type of effects is use today for live sound: reverb and delay.
Reverberation or reverb, as it is more commonly known, is perhaps the most
widely used effect. Natural reverb is created by sound waves being reflected
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 as 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 to the listener.
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 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
beginning of the first reflections being 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.
Tutorials 8
Digital Effects 8.6
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