Delay Systems - PRESONUS StudioLive III Series Owner's Manual

13 Resources
13.7 Using Output Delay
13.7.2

Delay Systems

Mains delayed
to backline
In most situations, a PA system relies on a main speaker system, positioned at the
front of the room, to reproduce audio for the entire performance space. As a result,
the level of the system is considerably louder at the front of the room then it is at the
mix position.
In situations where sound must be reproduced outside of the main system's
optimum range, well-placed delay systems can extend the intelligibility of the
front-of-house system. By creating listening zones throughout the room, your front-
of-house system only needs to be loud enough to cover the front of the room. As a
result, you can lower the mains level, give the front-row listeners' ears a break, and
get better fidelity from your speakers.
When placing delay systems, place delay systems where the main system's
intelligibility falls apart as it is overcome by environmental obstacles:
Inside. Indoors, you are trying to overcome the direct-to-reverberant reflections.
Your goal is to find where the direct signal-to-reverberation ratio has reached
about 50/50. At this point, the reflections in the room are at an equal level to the
direct sound of the P.A., and vocal intelligibility is lost.
Outside. Outdoors, you are trying to maintain level as the noise floor of the
crowd begins to be at equal level to the P.A. in the intelligibility range. At
this point, the main system needs more support in order to deliver the same
perceived loudness as you get further from the source.
The goal of distributed sound is for the people in the back row have the same
listening experience as the people in the front, but it isn't as easy as just bringing an
extra pair of speakers. To create a distributed sound system, you need to delay the
signal going to the additional speakers.
Front Fill delayed
to Mains
1. Once you have positioned your delay systems, measure the distance from the
left front-of-house speaker to the closest delay speaker (most likely, the left
side delay speaker). Divide the distance by 1.1 (if measured in feet) or 0.34 (if
measured in meters).
2. On your StudioLive mixer, select the FlexMix driving the output connected to
your left side delay speaker and configure it as a Subgroup.
3. Set the Output delay on your newly created subgroup to the result of
your calculation.
4. Repeat steps 1-3 with the right side of the system.
5. Once you have positioned and delayed your satellite system, use an SPL meter
to match the output of the main and delay systems at the measurement point.
For example, if you are standing 30 feet from the left side of the main system and
10 feet from the left side of the delay system, and the output of the main system
is 85 dB, then the output of the delay system should also be 85 dB.
StudioLive™ Series III
Owner's Manual
Under balcony
delayed to Mains
135